The hypertech and the Superchips tuners are good. I have used the superchips more, and alwasy seen results, but one word of advice..........
on a relativly stock application such as yours (meaning if you are not racing, changing cams, heads, ect), DO NOT ERASE THE REV LIMITER!!!!! They are there for a reason, mainly not blowing your car up! You can erase the speed limiter, and that is ok (although they are there for a reason, too. Usually it's because one part of your stock drivetrain is not strong enough to handle higher speeds than the limiter is set at, but if you are not maintaining those speeds for looong periods of time, you will probably be ok).
Anyway, good luck in your choice.