I've taken up to 1500 mg (not fun) and just got down to 900 in the last few days after being on 1200 or 1500 for about 18 months. I have never taken any in the day and I can't imagine doing that.

It definitely got less sedating with time and I don't find it all that sedating at all now (I'm writing at 1:45 AM and I took it at 9:30 along with plenty of other sedatives). The XR form was much less sedating for me and I went on that about the minute it came out and life got a lot easier then.

I had to go on very slowly over 3-4 months just to get to a therapeutic dose but once I got there it was fine after my body adjusted. I think overall it took 4 months to go up to a good dose and adjust so I wasn't quite so tired. Then XR came out a year later and it got much easier to handle even on the really high doses. Even 1500 mg wasn't sedating after the first 2 days.