Plenty of people feed live with no aggression problems. I personally feed frozen/thawed, as it's easier for me. Also, as others will probably tell you, you're actually more likely to have aggression issues if you feed in a separate tank - transferring a snake from one tank to another while in feeding mode isn't really a good idea. Also, it's a lot less stressful for the snake to feed in their "home."

So no, if done correctly, feeding live is perfectly fine! Hope that helps