The Halo TSA is only fractionally faster than a revvy - the main difference is that the paddles spin in whichever direction is best to feed balls depending on which way you're leaning.
The Egg is a good deal faster, but I've never had much luck with them, and still seem to chop on most markers I've used them on during sustained fire, even at modest ROF.
The Halo B is without doubt the fastest of the lot, although you'd better make sure your ball detents are stiff enough to cope with the pressure on the ball stack. Also, reliability has been a major headache for me and manyother people. Hopefully the Z code will alleviate some of the motor burnout problems though.
p.s. The rip drive won't make a Halo feed any better or faster, but it lets you manually load balls into the stack if it decides to die halfwy through a game. It is just a crank handle for the feeder cone.
