I always go for beefed-up stock rubber bushings, when available. I ran poly in E30s for 5-6 years, and it really was terrible on the highway. I think a lot of people, like me, ran poly to save $$$ since stock rubber ones need to be pressed in & that usually means paying a shop. When the poly went in, I thought "wow this thing handles amazing! poly = win!" It turned out that the old parts were rotten though, so I went back to stock after many years. Anyway, if you can find stock bushings that are solid rubber rather than webbed, go for them. They will last longer and offer marginal improvements to handling. Otherwise, stock parts are just fine. Some E36 M3 bushings are solid rather than webbed, but also more expensive too.