When I get rx'd Adderall, I take it "as needed," read: whenever an exam or term paper comes up and I need more inspiration, I re-dose.
When I got Vyvanse, suddenly, I didn't need to do that. 140mg (my insurance authorized up to 170mg; check with yours) of Vyvanse, which is equal to my Adderall 60mg/day, and I take it once and don't have to think of it for the rest of the day. I don't re-dose on it or even feel tempted to re-dose on it for 2 reasons: 1): I know if I re-dose after the morning, I can't sleep the next day. And my problem isn't taking a bunch at once when I wake up, it's taking more adderall as the day wears on. But 2nd reason): after 200mg in a day, Vyvanse stops metabolizing, stops cleaving the lysine from the amphetamine, effectively meaning you're pooping out unspent Vyvanse if you take more than 200mg/day. And the dose between what I was taking and 200mg was too marginal to justify caring about.
The only problem with Vyvanse is some might not find 70mg enough, as it's equal to 30mg of Adderall XR. If you take more Adderall XR, you have to find a doc willing to prescribe an equivocal dose of Vyvanse, which means for now working outside of the parameters of the PDR's recommended dose range. Luckily, many insurance companies authorize you for higher doses, like I said, mine lets me take up to 170mg, so call your insurance company before talking with your doc. it's not -that- expensive, though, although if you want to use Shire Cares and you're unemployed or make very little money to get approved for free Vyvanse from Shire, they only cover up to 70mg/day.
Vyvanse can't be metabolized by snorting or injecting it; anyone who tells you otherwise is also as stupid as the types who take more than 200mg to get "high" (aside from them not being able to metabolize more than this, they're likely confusing a mild mood elevation for euphoria, since the dose is too low to get euphoria from).
Anyhow, good luck, and stick with a long-acting stimulant of some kind, even if Vyvanse doesn't work out. Of course, in re-reading your post, I note you are the type of person who thinks he doesn't have AD/HD, despite seeking out stimulation from drugs 24/7, and feeling a buzz even from low doses of stimulants... maybe you're not fooling anyone, or playing any cards, and you need to just accept you may very well seek out stimulants because you probably couldn't pay attention in classes, had low motivation in school, this resulted in you not finishing college, thus resulting in a perpetual feeling of needing to escape your relative poverty/issues of failure/perception of failure in life, which in turn led you to seek out meth, all of which could have been averted had you had parents who gave you low doses of stimulants that let you do well in school by motivating you do so and helped you achieve success in school that led to success in work and other areas of you life. Too close to home?