[vhuntd]

I'll usually raise AJo out the blinds under following conditions.
If I'm the SB with one limper.
I'm the BB with one limper and the SB completing.
Two limpers and I'm completing from the small or checking the big.

With one limper situation one of the following things usually happens. An early position player limps with an ace rag and you have him dominated. If you raise from the SB you usually get heads up in a dominating position or force BB to put in more with a weaker hand. You usually have a pretty strong hand against one late position limper too. If you're the SB in that situation you can get it HU again. If you're the BB and the SB completes, he'll usually be doing that with a very wide range so you're getting EV.

However, once their are two limpers the hand is too hard to play OOP. You should just complete or check unless you feel very confident that you can outplay your opponents postflop.