I can comment on both, as I have both.
The banana pipe is alright - but it's power band is WAYYY at the top of the top end, took me about 1/5 - 1/4 mile for it to kick in, but when it did it was sweet. What would help it's performace would be if the stinger came off at a 45 degree and extended a foot or two to really get some top end gain. It's loud - if you want a loud pipe, here it is. This is not a midrange/lowtorque pipe, this is for WOT topping out. As well, it has a LOT of room to grow, if you can weld or have access to welding it would benefit from an inch or two on the header pipe so it kicks in a bit earlier.
The SBP pipe is great in that it is fairly all-around. It gives you the mid to low end torque to accelerate up hills, while at the same time gives a nice clean top end. Though, I don't think for a bolt on mod it gets as fast as the banana pipe at WOT. I do like the sleeved parts - makes it nice and easy to adjust as you need. As well, it's easy to get extra parts. I think it could stand to have some length cut off the header tube and it definitely needs a longer stinger - instead of a stinger it has a muffler, which is the first to go when I get a small grinder.