VP is my favorite overstable putter. As Prerube said... all Vibram discs are virtually indestructible. I prefer the medium X-link.
The Summit is a very good understable, shallow rim putter. I like it in all of the rubber/plastic compounds. The soft will just go straight, no matter what. It's my favorite putter for 35 - 60 foot "go for it" putts. Once it hits something, it stops. The medium and firm are great "slow approach" discs. They fly straight with very little power and land flat.
The Ridge is directly in-between the two.
You will like the Ibex if that is your choice. Solid, straight flying mid with decent glide. It will keep these characteristics because of the rubber.
The Obex is a beaded Ibex.
I like and carry all of these discs.
If you like "traditional" style putters, the Sole is just that. Slightly overstable and easy to get used to. If this was the only Vibram disc, I'd carry it. I do prefer the VP, but that's personal preference.
The Ascent is a solid fairway driver with predictable flight and fade at the end.
The Trak is a slightly more understable fairway driver with more glide than the Ascent.
Both drivers are easy to throw and control. I would call them both "control drivers".
