I use it on the piezo's of my BFR JP for the last seven years or so. I don't dare put a whole lot on there because of the fact that it is piezo saddles and I don't want to cause a problem gooping them up, but I've had no issues and it certainly helps with tuning stability. I absolutely put it on the knife edges.
Glad that BrickGlass has been successful with the piezo, I'd always been wary of recommending myself. Like he says though, don't put a whole lot on there, use the minimum amount necessary (a little goes a long way).
I used to lube knife edges but stopped. There is no sliding motion on the knife edges, it's a pivot/rotation about the contact point of the knife edge so there is no sliding friction to overcome. (On vintage strat-style six screw bridges, lightly lubing the smooth part of the shaft of the screws is helpful however.) Besides, over time the goop attracts dust and grime and needs cleaning so I'd suggest using pencil lead if you really want to lube the trem posts.
In general - a very little bit of Big Bends goes a long way. I have had it deaden string vibrations.
Personally for the most part I have been using a very small drop of Tri-Flow Lubricator in my nut slots, on the saddles where the strings break and occassionally on the pivot posts of the bridge. I got one of the pin point lubricators - the tip is very small and it allows a very small drop to be placed, then I work the trem a few times and pat off the excess with a paper towel.