I've been taking Bupropion(generic) for 3 months. I've tried 300mg-XL, 2x150mg-SR, and both times (though I'd take the morning dose at 6AM) had a hard time falling asleep at night, tossing around in bed an hour or so. I normally don't have a sleeping problem. So, I now take only one 150mg-SR around 7AM and no afternoon dose. I can fall asleep fine now, but my energy runs out in the late afternoon ...