I've not run the BRP, but everyone that I know with one loves them.
I have run M18's since the beginning, and they are nearly indestructible. the Pro takes all the great aftermarket ideas and puts them in one package, so I recommend it highly.
The LRP and Vendetta both appear well built, but they are way to heavy to compete with the M18. The 18R is even worse. They should only race other 18R's
As for the Recoil... there's a good reason for them being discontinued.
I've been told the Scalpel breaks a lot of T-Bars, and parts are hard to get.