ECA for me. I try not to use it more than once or twice a week though. I usually save it for the days I don't get much sleep due to school and work. The days I use it... I have FREAKY work-outs.
have only tried eph and caff but for me its definatly eph, it makes me so focused. I try not to use it more than once per week though because it seriously disrupts my sleep paterns and also i struggle to eat on it aswell!
Have you guys tried Thermo Pro by Prolab. Two tabs of that and Im so focused and buzzed its amazin. Much more than on zenadrine. I havnt tried NYC yet though,
Brooksy