Pros: If you are looking to test yourself this is about the best game out there. Not only that but it has a wonderful SP campaign.
Cons: Every major complaint I've had has been fixed via patches ( mainly battle.net features ).
As far as the single player campaign goes, it has a lot of varied missions, as well as selectable upgrade paths making one play through completely different from another. With the addition of achievements you are rewarded for your hard work.
I was a huge SC1/BW fan and Starcraft II lived up to it without selling out on what made brood war so special, yet modernizing just enough to keep it perfect for today. Can't recommend enough.