When are you flying? BOS and SEA have some of the longest TSA lines in the country. I've waited over an hour in line at both. I've gotten through BOS in 20 min but that's the exception, not the rule. AUS has gotten a lot worse too.
I fly in the morning and usually on Mondays and Tuesdays when I do fly from BOS. Departure's are usually in 7-8AM time frame. I've never had an issue getting through quickly. Maybe I'm just extremely lucky.