Nuna - PIPA next

I would say that it depends on the case. In general, it is better for newborn babies to lie flat, so if you are planning on using your stroller for longer walks, it is better not to use the car seat for that. But if you will be using it primarily to go from your car to the store, that should be fine. But it is also worth checking if the convertible seat is really fully secure for newborns. Yes, they are rated for such and have inserts, but how tightly does it fit newborns and what angle is the baby positioned at? At least here in Germany, the typical advice is that infant carriers are safer than convertible seats for newborns. (But seats vary a lot by region, so this may not apply outside of Europe). As for me, I am in a different position this time (it's my fourth pregnancy), as we now live in a major city and don't own a car. I ended up getting the Nuna Pipa Next infant seat as it is very lightweight and therefore easy to move into a taxi, car-sharing car, or rental car on the rare occasions that we use them. We don't intend to use it with a stroller except perhaps on vacation. I did consider just starting with a convertible seat to save money, but decided against it.

Yeah, I live in a big city and also don't own a car, so I will likely barely use the seat. I bought a Nuna Pipa on sale from Babywalz for €135. I chose it because it has a relatively high weight range and my older kids were big when they were born. It is also doesn't weigh much so it is easy to use for car sharing. It was a model that was already discounted due to the color, I had a €10 gift card, and they were having a 15% off Nuna sale for one weekend only. According to their website, the exact same seat costs €220 at Zwergperten, but the German-speaking parenting internet would still view the decision to purchase the exact seat (**in advance, not after renting a seat first!**) for €85 cheaper as being terribly irresponsible. I mean, clearly the seats become magically less safe when purchased from an unapproved vendor. The proof that this happens is that the Fachhändler say so! And the Fachhändler couldn't possible be motivated by the profit that they make from convincing worried parents that they should buy their seats at inflated prices. They are purely performing a public service! And if it would actually common for infant seats not to fit full-term, normal-sized newborns, no seat on the market would be suitable, as a baby that is shorter/taller/slimmer/chubbier at birth could easily not be so after a couple of months, and then they could need a different seat a month later.

The Noona is probably the best car seat that turns into a stroller - it’s an all-in-one. So you don’t have to worry about bringing along a separate stroller. It is great for the first year or so. And the Noona is stroller is small so you can easily bring it to wherever you’re going without it being a hassle. The ones like Uppababy Vista are good too, but it requires you to bring a separate stroller that you can click the car seat into. But once the kid outgrows the infant car seat, the stroller is just a large stroller and doesn’t really have any major benefits over any other stroller. I’ll say this - we used the Uppababy system for our first two kids then did the Noona for our third - and I really wish we had gone for the Noona in the first place.

Nuna makes an awesome infant carrier we just got two bases

I have a Nuna Rava forward facing behind the driver seat, and a Nuna Pipa rear facing behind the passenger. Both front seats need to move forward from where we'd normally have them to accommodate the car seats behind. I'm 6'2" and when I drive, I do need to move the seat forward a good amount from my normally position because my 4 year old would other wise have only a couple inches for her feet. There is not room to comfortably fit a third person in the middle seat of the second row I'd say. And no easy way to get to the third row with two car seats installed.

We have one but honestly the price tag just doesn’t make sense unless you’re really sold on it and it fits your stroller needs. We really liked the concept of being able to use it without a base, but the way it functions without the base is pretty annoying (strap across lap). It’s light, but they all get heavy fast, so that’s similarly not something that rises to the price tag, IMO.

Nuna strollers and car seats with specifically the merino lining. The lightest version of the Pipa that had a reflex clip in base and could be used without the base. Things that we got after attempting alternatives because we love traveling: A dedicated travel stroller that fits in the overhead of airplanes. Cybex libelle. The travel bag for the nuna pipa car seat. The seat is light and so it’s a good item have as a backpack. You can also jam a load of diapers in the space saving previous suitcase space. Baby Bjorn Travel Crib. It’s so light and easy to set up. Gave us much more options for locations we could stay.

Hey, I am basically you, but a year down the road. I live on the second floor (no elevator) and don't drive. I have (and recommend) the Nuna Triv Next with the regular Pipa car seat, which has the longest life of the Pipa line. You might be able to find an adaptor on Etsy for another car seat.  I used the carseat in the stroller until my baby was about eight months and could sit up independently in the regular stroller seat. No base is required to be installed in the stroller or in the car.  The bassinet attachment option isn't approved for use in my country, and I was fine with the car seat in its stead.  The stroller itself folds up with an easy pull and lift of the handle. This can be done with one hand. It's light to carry up and down the stairs, and when folded takes up hardly any room.  Upside: The stroller seat and car seat can be set to parent-facing or world-facing. The Minu does not have this functionality. (Don't know about the other one you mentioned.) Parent-facing is great because you can look at them, talk to them, keep an eye on them, and see what they're looking at. Studies have shown that young babies in world-facing mode experience a lot of anxiety. They also can have delayed language development. Many benefits to facing your child!! Plus they are cute af and you'll want to look at them.  Downside: The basket has only a 10 lb weight limit. The mesh is not nearly as sturdy as those I've seen on the Uppababy line.  Let me know if you have any questions! 

The fact that my Nuna weighs less than 9 lbs is why I own it, every person who’s ever grabbed the seat has complimented how lightweight and easy it is to maneuver. And I’d buy it over and over again!

CPST- feel free to PM me for more details or suggestions. Basically some of the more expensive brands are more complicated to install or are outgrown more quickly. For instance the nuna infant seat needs a rolled towel to get it level in most vehicles. Uppababy infant seats are outgrown very quickly. You mentioned Clek but Clek is one brand that is very recommended by techs. I own 3 of them myself. The Clek liing is one of the most highly recommended infant seats on the market. We couldn't use it in our vehicles because we have Ev's but that would have been my top pick otherwise. We own 3 Clek foonfs. The Clek also has adaptors for uppababy strollers if you go that route.

Which seat? The harness height on all of Nuna’s seats is SHORT. If you have a tall kid they will outgrow the seats earlier than expected. For us the infant seat was also short-lived because my kid started hating it by like 5 months and we switched to convertible , so that felt a waste to me. Also Nuna’s textiles stain, discolor and sun bleach super easily and look terrible. I am learning that it’s more common to have to replace a seat due to damage from something like frequent accidents or sickness /body fluids because there are so many dang rules about how to clean and you cant use basically anything, I would say Nuna is not worth the money.