I tend toward the caffeine tabs, never was a big coffee drinker..
with tabs I can measure the exact mg dosage.
it also my "pre-workout" booster, and being a late night trainer, that does cause sleep problems.. but thats what sleep meds are for. Of course Im under NO illusion that this is healthy.. then I really dont care as longevity into old age is not really any kind of goal personally.
fyi, the best energy booster I use for working out is the old standby ECA..ephedrine/caffeine/aspirin..