Same same (pro D Magnet). The only time I switch putters is when I'm driving or doing upshots . At that point, I pull a FLX Challenger. I will say that the Magnet's knack for going over things (jump putt or elevator) is what made me choose it as my primary putter in the first place.
I find that a lot of people--including top pros--like a bit less stable putter for most jump putts, which also seems to match what Sean said for straddles as well. Thus, for jump putts I pull out a fairly beat XD that I've had for some time because it holds a line well and won't hyzer out too early. I'll bump it up to a bit more stable (newer) XD when it's windy.
This guy knows what he is talking about!!!! Its all up to the person though and I pesonally use all my putters depending on wind conditions and length of the shot. I tend to use my black DX Aviar for longer jumpers. I have canned more inside of 60' with my 5X JK Pro Aviar than my with my Champion Rhyno. A local pro at my course absolutely tears it up on jumpers with his Gateway Wizards in different stages of beatness.