Pros are it runs pretty much the same as gtaiv and all, one con I noticed so far (pc version I'm playing on) is that multi-player models are lacking. Theres not many selections to choose from to customize your appearance as in GTAIV. Pros = the apc, skydiving, higher chopper altitude, some cool new vehicles+chopper+new weapons.
Heres a short clip from some multi-player action earlier tonight with 3 friends in free mode when we had a 6 star going for about 30 mins or so before any of us died. lol.
(and yes its taylor swift metal version hahahah)