Definitely get the Maverick.
It's so accurate... Small and lightweight too. Good for stealth/mobility and targets within 15 yards.
Invest in something with a large clip as a back up.
Trust me, accuracy is the thing you want, but for a wide scale game, you'll need a back up, and that back up will need to have a ton of ammo. So, semi-auto something with a decent magazine or clip or whatever.
Don't get the semi auto revolver one with 10. It's got terrible aim, and it's not that strong. The shotgun has 10, and better range, but it's a pain to reload, and not accurate. Good for wide spread play though, since you're bound to hit something if you have a bunch of people coming at you.