I am not a fan of VPP bikes. We have had a ton of trouble with bushing issues, and squeaky rides. They also a feel that I am not that fond of, as they don't seem as plush as a 4-bar or get the claimed travel. Lots of people like them, though, although VPP bikes in general seem to require a bushing that is better designed for the rigors of VPP pivot travel than whatever they are using. I have yet to ride a VPP bike that didn't get squeaky in a short amount of time, especially with the volcanic dust that we ride in.
I generally like the feel of a 4-bar type suspension (both Ventana and Turner are modified so that it doesn't infringe on Specialized's patent), and I have had good luck with a few single pivots as well, and find them to be low on maintenance. I have had 3 Ventanas and 1 Turner the past few seasons, and I didn't even have to swap out bearings or bushings once. They were dead quiet, as well. My current ride (when I get healed up, that is) will be a Niner RIP9, which is a slightly different linkage, but rides somewhat similar to a 4-bar design (plush and fairly linear).