The frames will all be great. Specialized and Rocky Mountain are big companies so they put great quality into whatever they make. Plus, they will all have a good warranty, as long as you buy from a reputable shop.
Sorry Patrice. We get a lot of spam posted to the forums, and this particular post was loaded with links to bicyclesquilicot.com. Admittedly I’m not familiar with bicyclesquilicot.com, and seeing those bikes listed for sale online raised red flags for me. But as you pointed out, listing Specialized bikes for sale online is OK, as long as they’re picked up in store.
Aside from the models that you are looking at, I would tryout a 29er first if I were you. At 5′-4″ it may be a bit too tall and not as comfortable as a 27.5. I am 5′-8″ and much more prefer a 27.5 or even a 26 over a 29.
I can advice you fat tire bike,if you are riding on off road and in the city.The closest relative of this model is a hardtail mountain bicycle,so you can use it in mountain riding too.Check this article if you need more information https://bikesist.com/best-fat-tire-bikes/