you can run any dj05 or DL09 kernel with DL09. As for the speed boost, I am not sure about that. SF kernels were good but they did not give any speed boost. I used them all and JT's 12/30 is just as good or better. The later sf kernels did not like my battery.
I pretty much run stock w/ touchwiz because I like it (Minus the verizon bloat) ontop of StupidFast, with the latest test kernel (12/20/10 I believe). It's actually been pretty stable and reliable, even more so than the current "stable" StupidFast kernel IMHO
I am using adrynalynes 12/30. It works great. Great battery life. Plenty snappy. I have tried just about every kernel out there and adrys 12/30 is over all the best for me. I tried Sf 12/19 because it was over clocked. I did notice a good bit of a speed increase but my gps wouldn't turn on.
SF 12/20 is stock speed, just undervolted. SF 12/19 is overclocked and undervolted with a few minor issues to date. I found 12/20 to be pretty quick but after 48 hours battery life dropped off considerably. I've sense switched back to my old standby of 1.54. Like 12/20, it is stock speed and undervolted, just not as much. Rock solid, very snappy, and great battery.