I would have to agree that if you are consistently working large venues you will need
2 L1's and 4B1's for the Bose System. My suggestion is to go to the bose KJ/DJ forum and read up, or ask the question.
If you are working say up to 400 you can accomplish that with one L1 and 2 B1's which is what I have for my setup
You will be amazed at how many top level professional DJ's have made the switch to Bose L1 systems. Many of them cover 500 to 1500 person events with 2 L1's and 4 B1's and have plenty of headroom and low end, even for teenyboppers. Actually the larger the room the better. The performance outdoors is astounding. Reports coming back from the DJ's and KJ's alike are very impressive.
While originally this system was tailor made for the professional musician it has been adapted to DJ/KJ applications quite handily.
I researched Bose of 1-1/2 years before taking the leap. Their forum was very helpful in making my decision. Read back as far as you have time for as there is really great information there. I found that by reading there I knew far more than any guitar center rep would ever know about the system. I found demo's there to be less than thrilling as they did not understand how to properly adjust the gain staging that is critical to getting the sound and headroom right. After reading the downloadable owners manual I was able to go in to GC and make that system rock.
heres the link:
http://bose.infopop.cc/eve/forums/a/cfrm/f/3961033894
There is a fellow by the name of Cap Capello on the forum He is specailizes in large venues in many of New Yorks grand hotels and venues. His phone number is listed there and I recommend you give him a call and discuss your needs with him. He is also a Bose Rep and is extremely helpful. This guy is a pro and knows our business well.
PM me if you would like to chat.