I got it running yesterday with the Mamba Max 7700. It is rediculously fast. I had the timing turned all the way down and had it geared with a 15T/93T. It was almost as fast as my friends Traxxas Rustler with the VXL on a 3s lipo.
I then swapped the pinion and spurs out for a 17t/83T and it is getting a bit insane now. I was pulling a couple of wheelies when I could get traction. Also shattered my first antenna tube in a flip. I am going to gear it down a bit today to play on a bike track, but it is a lot of fun.
So to answer your question, I think you will be fine with the VXL System. I havent had an issues with the stealth as of yet.
Current Project: RC10 Worlds Car Rebuild
Weekend basher: 2006 Wingless Subaru STI
DD Beater: 2008 Ford Focus