Calling a 3bet with AJ

I am fairly new to poker beyond the occassional home game or visit to the casino. In 6handed micro is calling a 3bet with AJ going to be +EV? I play RUSH POKER at the moment so its generally more about position and betting patterns versus STATS and NOTES. How important is position when calling with AJ? Am I looking for an AJ flop when 3bet or do I have +EV agaisnt if I hit my Ace agaisnt 99 to KK and AT Ax suited? Although I don't think some of this range with 3bet always 3bet. Lastly if your UTG or UTG+1 should you open with AJ?