Unless you're doing significant cold, snowy winter running, skip the GTX model. Your feet will be sweaty, and if they get wet they'll stay wet.
Outside of that, the Altras are going to be a huge change from the Ghost. You're going from a 12mm drop to a zero-drop shoe with a pretty significant change in the shape of the footbox. Have you ever run in zero-drop shoes or tried the Altras out yet to see if you actually like them?
Unless you're doing significant cold, snowy winter running, skip the GTX model. Your feet will be sweaty, and if they get wet they'll stay wet.
Outside of that, the Altras are going to be a huge change from the Ghost. You're going from a 12mm drop to a zero-drop shoe with a pretty significant change in the shape of the footbox. Have you ever run in zero-drop shoes or tried the Altras out yet to see if you actually like them?
GTX is goretex for 98% of trail running not worth it and usually leads to sweaty feet. If you using them for winter snow running maybe… as long as you can keep all moisture out. Often deep snow will get into the shoe from you ankles and then it will simply stay wet. Same with rainy trails as water will run down your legs and into your shoes and same issue.
Good for soccer coaches standing around in wet grass. That’s about it IMHO. Better tonget some good synthetic/wool running socks that help wick moisture away from your feet.
I think you'll have better luck asking in r/AltraRunning
There will be more people who actually know about these two models there, but also they don't mind answering q's about similar shoes in my experience.
But to answer your original question, I've been trying on the GTX shoes from Altra trying to find a pair for winter. They used to waterproof their non gore tex models but they don't seem to anymore. I have really wet slushy conditions where I live. The snow clung to my LP7 and made my feet too cold.
The GTX LPs are made on the same base/outsole, but the upper material itself isn't as flexible. Like someone else said, it's more snug.
But also the upper seems to be slightly different. I tried on the Timp 6 GTX versus the Timp 6 and I was so disappointed that they moved the heel collar just enough so that it rubbed my ankle knots, whereas the non GTX version did not. I don't know if that's the case with LP, it's just a heads up.
Also my experience with gore tex is that it's a more fragile fabric, so it's more prone to failure. It's not breathable, either, so if you get sweaty, you stay sweaty.
I would recommend using the LP as a hiking shoe only for a while. Sticking with a 3 mile hike at a time would be a nice adjustment to zero drop. I think that forest trails, due to being naturally uneven surfaces with plenty of give, don't challenge your legs in zero drop shoes as much as on pavement.
I would not take the LP on pavement because that will wear down your lugs. You can wear them on pavement, and they will be quite comfy, but those are pricey shoes to be wearing them down prematurely.
Even after hiking for 2 years in my LP, when I tried to run in them I also got Achilles aches. Likewise, when I transitioned to zero drop shoes all day every day and got plantar fascia pain.
The good news is that I added in foot, Achilles, calf, and overall leg strengthening exercises to my routine, and I no longer have that problem. It took about 4 months of consistency to adjust. I did squats, RDLs, heel raises, toe-ga, toe curls, and hops. I can send you videos if you want.
If you're new to running, run in your usual running shoes. If you want to transition to zero drop, you have to take it a little at a time. Start like you're learning how to run again, like C25K speed.
Also check out these subs if you haven't already:
r/AltraRunning
r/BarefootRunning
r/BarefootShoesTalk
Agstroh
