I'd say it depends on your discipline more than anything. Tactical crowd seems to heavily prefer MRAD, paper crowd seems to like MOA (although I know almost nothing about F-class and similar, but there may be some MRAD there too). So if you're thinking of shooting some PRS I'd recommend you find an MRAD scope. If you have spotter help every time you miss they'll be saying stuff like, "you were left about three tenths" and you'll have to either convert in your head or spot your own miss. I have MOA scopes, but when I shoot a match it's tactical, so my scopes moving forward will be MRAD.
Another nice thing about MRAD, is the scopes tend to come in 10mrad per revolution, vs 15 MOA per rev. So if you're shooting far enough to do more than one revolution, it's nice (not critical granted) to have the last digit of your dope line up with what you dial. For example, if you have to dial 27 MOA, your turret is on the 12. In a time limited engagement this is a challenge. Vs 10 mrad scope where if you have to dial 12mrad, your turret is on the 2. Even worse than a 15moa per rev scope is something like a 12moa per rev scope (had one of those once). Again if you're under 1 revolution none of that really matters. You can always mark your turrets with the next rev numbers too, which helps.