The only Rolex rep that is a potential time-bomb is the Daytona line and that is because of the movement which is modified with a few extra gears to put the seconds @ 6. You will find only few Daytona owners who have not had paperweights in their watch box at one time. Another watch that might be troublesome at times is the CHS (Correct Hand Stack) GMT. All other Rollies are technically pretty basic watches. What you should buy depends on your taste and budget. There are good Subs and SDs (of course), good Yachtmasters, the Millgauss is a good rep. The vintage Rollies usually require a few mods to be convincing...
Bottom line: Rolex is THE most copied brand of all watches, so the choice is yours..