I was on it for 3 years? Maybe less maybe more. During that period I quit it once, changed dosages several times (was between 200mg -400 mg, settled on 200) and had various add on medications.
Currently no medication. Why? Eventually started to feel dulled out, still had mood swings but, I couldn't really experience them. I'd be only somewhat anything and when "meh" is all I feel, I could even go for some depression. I did find since quitting medication my ability to concentrate is not as good but, I was super human when it came to concentration and multitasking before so, now I'm just human!
If I want something to take the edge off, medications are fine but, long term? Not worth it for me.
Other than feeling like my soul was anesthetized, no effects worth noting.