what is it, suspended release and extended... somethin'...
explains a lot right? anyway, i know it's something like XL (the newest form) you take once a day and it extends the dose throughout the next 24 hours and SR (older form) seems to have a shorter span of time it covers, so you take it a couple/few times a day.
all i wanted to respond with (in case it's of any help to you) is that in all my researching of people's experiences, stories, it is ultimately going to be you finding your own truth; finding which is right for you, with your body.
the stories/experiences have all of their counterparts, one person who took the SR form, lost a few pounds, then switched to the newer XL form so they only had to think of it once a day and then put ON a couple pounds.
so for every answer you think you've found like that, there is the opposite story out there too. some people lose a little weight, some a lot even without trying and actually complain about it!
some people don't fluctuate at all. and some people gain weight. i've only been on XL for about a month now. and i've stayed the same so far. the first two weeks i gained 3 pounds, and in the last two i lost those. it's supposed to be a weight neutral drug, but i think whichever one you choose, give it at least a month before you assume how it's going to affect you. i REALLY wanted to switch after those first couple of weeks, because i was so super-afraid of gaining any more weight. my appetite seemed to have increased and i was convinced it was affecting me in an opposite way than anyone else i'd read about with their suppressed appetite. but i gave it more time and have come to find, i'm right back where i was with my weight when i started.
oh, and another curious contistent reporting was that some people needed to work up to the 300mg a day until they felt the full affects (energy, motivation, weight loss) i'm currently still at 150 a day so i can't speak on my experience yet.