I almost considered doing the BP-51's when I swapped suspensions last week. I was running Bilstein 5160's and Rough Country springs. After about 40k miles, and all of the weight I've added to the vehicle, that suspension system wasn't cutting it.
I just ended up doing the OME Nitro's with their Heavy Duty spring set, and 600lb rear springs. No other experience ever with OME products, but it rides and handles MUCH better than it did.
Still wish I could have went with the BP-51's. I'm sure you'll really like them if you go that route.