I would recommend not buying this game whatsoever. As a life long call of duty fan it's upsetting to see them ruin what was once one of the best franchises to exist.
Between the overly strict skill based matchmaking and poor connectivity issues (especially with PC), the experience of playing this game is a 3/10 at best. $70 for content that was created back in 2009 is ridiculous, and there is zero wow factor to any part of the game.
I was expecting the worst with MW3, specifically with the multiplayer, and it's exactly what I thought it was going to be... Terrible.
The campaign was also a massive let down and overall, save your $70, and stop supporting a company that doesn't give a single care in the world about their fans, especially their core fanbase that got them to where they are. Call of Duty has become one big marketing scheme, and it needs to end now.
This will be the last CoD I buy.