I still haven't opened it.

I think I'll actually play it in the next few months, but still enjoying MWR too much to change.
Better get started because ranking up for certain perks and guns you will want takes days and days of gameplay. I have 10,000 kills and only on level 31 and it takes painful time to rank up especially when you get to level 20 and up. I want to get to level 36 for lightweight/lightfoot for a bit quicker run speed for example. I will never get to the final level most likely unless I quit playing Blops where I have 10,000 kills too and probably still never get there. I am thinking about devoting more time to this game. Starting late in this game means you will play players who have ranked up and have access to more perks, guns and most importantly in game experience and have figured out their ideal settings etc. Although you can get very worthwhile perks like heavy hitter early on and the early guns work just as well. After playing Blops and Goldeneye with less lag shooting, for me it is hard to go back and play older games with more lag shooting for any extended period of time. Post your FC when you get started...