I think the BE's are a little louder with the same settings on the amp and bass. I haven't compared them head to head in the same environment yet. I can certainly hear myself better with the BE's, but that may just be the way they are tuned vs. the Aggies. I do assume since the BE's are 103db vs the 95lb of the Aggies...plus the 15" vs 12" that they will be louder.
As for bass output, I was pleasantly surprised. I like a lot of low end, to the point where I usually boost my bass controls slightly on both my amp and my bass. Playing with the GS112's, I had to roll back the bass on STL to about 9:00-9:30. Anything over that was a little flubby sounding and got lost in the mix. I had a good amount of low end still coming through though.
With the BE's and STL on the same settings (for the Aggies) I felt the bass was lacking, so I turned it up to about 10:00-10:30 which brought me right back into the same territory but with a fuller sound probably due to the punching mids. My solo tone was great, but it really shined in the mix. I cut through like nobody's business, yet still retained a very nice amount of low end. No flub, just defined tightness. They handled my low B great as well.
I was unsure about getting the BE's in the first place. I read all of the threads on poor port design and lacking low end, but I also read all of the stories about them sounding great. I couldn't pass them up for the price, and I'm glad I didn't.