Hey Wellbutrin,
This is a harm reduction focus forum, and probably not the best place for such a poll. Read the OD Guidelines (found in my signature) and you'll see why this thread is not appropriate here.
You should not exceed the maximum daily intake of caffeine and any other active ingredients or metabolites of stimulants, as they have many undesirable (peripheral) active CNS effects. Hypertension and Tachycardia can result, as can other less severe, yet prominent side effects like feeling jittery, shaky, dysphoric, changes in libido, irritability, GI upset, insomnia, anxiety, etc.
So you need to factor in the maximum daily intake for caffeine, a simple google search will help you with this depending on your location. IIRC in the USA they sell both pure caffeine powder, and OTC "stay awake" pills like No Doz in dosages of 200mg/pill IIRC, etc. I've never been a fan of caffeine though, I avoid that shit like the plague. I just do not like the feeling of caffeine, nor do I enjoy the taste of coffee, so decaf is not an option, I just avoid coffee altogether.
I really enjoy tea though! Why would anyone want to consume large amounts of coffee? For a product that is gross, stains my teeth like nicotine, and makes me feel like shit, when we are on a road trip and I'm driving and you say "Hey there's a starbucks at the next exit, can we stop?"
the answer is, a disapproving look, and a loud and clear "Nope".