I really like the way I feel on clen now. When I did my first few runs it was super uncomfortable. Now it's kind of a “PED for work". I can think more clearly and faster, I can express myself more fluidly, I have more energy, I can get by and still do cognitively complex tasks on lower amounts of sleep when I'm on it, and I can write more clearly and quickly. I live in China and I feel like I can speak and acquire my foreign language much better when on clen than off.
If not for potential long term heart effects I would run this shit year-round as a sort of nootropic, irrespective of it's effects on body composition. However, the withdrawals are brutal from it. I also feel a little bit disinhibited and more willing to express how I feel while on clen, the same thing a lot of people report with alcohol which I personally just don't react well to. I will sleep 11-13 hours a day when I come off clen, I'm demotivated, barely have energy to train, can't think quickly, impaired short term memory and language/mathematical ability.
I kinda wonder if it's even been studied in the capacity of cognitive enhancement/nootropic.
Ephedrine though, despite being reportedly weaker, turns me into a rage and anxiety fueled basket case who could rip somebody's head off over small perceived infractions. I don't go near that stuff.