Makes me extremely happy, sociable, energetic, and fun when tweaking or even slightly high I'm content, but when I crash and temporarily have no money for more, especially with no benzos or booze, things get really depressing and pleasureless for me, like just being a mind and body, no soul, like an android.
So it has made the highs in my life much higher and the lows much lower. I've tried to quit and go back to a moderate baseline but I can only ever make it a few weeks at most before I relapse, so fuck it, let's get high!
Oh, I've also stolen from friends, lied to family, mistreated authority, shoplifted, bought and resold, and done just general desperate things like having sex with whoever for money or not advancing my life as I should. Has made me look a bit older I think, and slightly more acne, but no real scars or anything.
On a positive note it has helped be very physically fit and attractive (helps you not eat so much and motivates you to exercise + boosts metabolism), lead to a lot of friendships with people I'd be too shy or anxious to approach and talk to otherwise, as well as some really good memories being the life of the party, the cool person, and having spiritual experiences with it.
But it has also lead to hospitalization in the form of psychosis and alienated me from some people who were good but simply didn't understand it or like me staying up for days on time eating nothing, then crashing eating all the food sleeping all the time and turning the place from super clean (I get really organized on speed) to a pigsty I simply have no energy to clean... and the withdrawal is horrible, you just can't think properly and while you don't feel sick, you just have no pleasure much or anything.
Would I recommend it? Personally I would not. I would seriously suggest sticking to coffee and cigs for stimulants, as these provide basically enough pleasure for those who need to stay awake or alert, without making you completely fucked without it. I mean even caffeine or nicotine withdrawal you might get irritable and stressed or low energy can't think straight etc, but not fully depressed and suicidal.