I'm a huge fan of Ibis bikes and the DW link suspension. The carbon Ripmo (V2)
is a sweet bike. Not too different from last version, but I do like it better. I'm not familiar with the AF since it is a slightly newer offering. If it follows suit with the new Ripmo (V2) and Ripley (V4), I'm sure it's a great bike. My pick.
The new Hightower is also a sweet bike. Slight change in geometry, frame, and shock. Bridges gap between prior Hightower and LT version. My bro rides this and loves it. Don't know much about the Jeffsy...
If it were me, I would extend the budget just a little and get the Ripmo or Hightower in a carbon. If you absolutely can't make that happen, then I would probably go:
1. Ripmo
2. Hightower
3. Jeffsy (someone mentioned a Canyon... I would definitely look into that as well...)
You could look to find a deal on a used carbon framed bike. But I can understand going new since you have identified the Ripmo and Hightower, which have both recently been updated. I think it's worth it to hold out for the newer versions of both (they both get such great reviews). I doubt you find either used at a great price yet. If you need some helpful reviews, check out yumyum's reviews: