Another point to mention from Bryan's review of the 200/1.8: it's very front-heavy, making holding the lens awkward. It also has a front-mounted tripod ring, which means you can't put the hood into the stowed/carry position if you have anything on the tripod foot (monopod direct-mounted, Arca-Swiss plate, etc.). Neither of these are show-stoppers, but I'd absolutely pick the 200/2 over the 200/1.8 if it were me.