I've only tried Ritalin and Adderall, both in small 5mg doses (at max 2x per day with breaks on weekends).

I've found personally that switching between the two every 5-6 months seems to be a productive course of action. I have not encountered any need to increase my dose due to building up a dependency.

pretty much tried them all, dextroamphetamine and methamphetamine work the best for me. Adderall has too many physical side affects for me due to the levoamphetamine which stimulates the parasympathetic nervous system. Examples being twitching, tachycardia. All of the fetamine's do the same e.g Vyvanse. Dextro and methamphetamine are the most effective at targeting the CNS, with methamphetamine crossing the blood brain barrier in higher amounts at lower doeses. Therefore methamphetamine in the form of Desoxyn has the least amount of side affects, for me while providing me with almost super human clarity.

Keep in mind that if you are taking ADD meds and looking to switch meds, some doctors can be pretty funny about Desoxyn, it's an old drug, not many know about it, and some docs see Meth and freak out. That being said, it's no more dangerous of a drug than Adderall is.