When you buy a suit or a pair of slacks with unfinished legs, they need tailoring (astonishingly enough, I saw a pair of suit pants on a fellow the other day, downtown, which had not been hemmed at all). You can either get a cuff, like this:
or no cuff. My rule of thumb is this:
If the pants are pleated, get a cuff. If they're flat-front, don't get a cuff.
I think it is slightly safer to have flat-front pants with a cuff than to have pleated pants without. That said, none of these options is outlandish, so if you have vivid fantasies of your new flat-fronts with a cuff, go for it. That feeling of confidence and style goes a long way in making sure the feeling is infectious.