I've been pretty happy with Alarm. It didn't rip my guts up like Super Pump, but I felt like I got better workouts from SP (as long as I stayed away from cardio.) I felt a lot more alert with Alarm the first few times, but built up an immunity quick. Taste (watermelon) was really pleasant compared to almost everything else I've tried.
I'm going to try some of the stuff that's been mentioned in here. Sounds like you guys are getting some killer results with stuff I've never heard of