I stayed at BA (Caribe Blue) back in March.
First time to Cozumel to.
I am planning on going back in 2010 about the same time.
To me, the place was perfect, it was EXACTLY what I wanted and for a great price.
Yes, it is not a 5 star place, but I was there by myself (wife does not dive) to dive only.
I noticed the street noise during the day. I dont really remember hearing it at night, maybe the air conditioner drowned it out. But it was NEVER a problem for me.
The staff rocks. Hotel and dive shop. Jorge was my dive op all week. I hope he is there next time, the guy was really cool, nice, and knowledgeable.
Food was good. Seriously, for a single diver on the budget, you cant beat the free breakfast and lunch.
Like I said, I will always come back to BA.