I've never ran it consistently more than 2 weeks but that **** is great. I'd start at 500mcgs , I've used it up to 1mg and it is a pretty big difference. .5 mg will get me the preworkout strength benefit where everything just feels lighter. Then 1mg gives me full on tunnel vision , aggression to the point I have to tell myself to breath and walk away from little things like someone using a squat rack and taking a little too long between sets and strength is noticeable . Now when I ran it 5 days a week for 2 weeks i did start feeling hotter all day and night , and leaning effect was there . One thing I'll say I'm not sure if it's because I know I took it preworkout or comes from the mtren but when I leave the gym the days I use it I really feel like I left it all in the gym, I feel completely drained and my stomach becomes a bottomless pit and then all I wanna do is sleep , again that could be me pushing a little harder since I took the mtren or it could be the mtren causing it but that's just been my experience with it . Hope it helps , feel free to pm me with any questions too