Theres nothing bad about it tbh I got bored of BF3 since you can litterally just farm ur lvl and ur max lvl in one day.
I prefer Games on PC then consoles soo Im not sure at all for your case. Don't mind the BF3 fgts who want to drag you along with their opinion.
It's definitely not worth paying 60 USD/EUR/£ for this game. If it costs ~25 USD then it would be okay i believe. Theres almost nothing new from MW2. You have a horrible FOV from about 60, you can't see shit and you can't change it. Matchmaking is for consoles not for PC. Theres no reason to use non ranked dedicated servers, totally useless. I bought BF3 a week before MW3 came out and for me BF3 is the best shooter i played so far.