First, you might want to start a different thread for just that subject. No need to hijack mine.
Second, you've asked a question that's pretty similar to, "Do you know the price for a station wagon?" Are you looking for vintage or new? How much do you want to spend? What kind of music do you play? Do you have something in particular in mind that you want our opinion about? What's your expertise level?
Helen, Groovekiller, Gandalfe, and a few other folks here own and/or have used a variety of makes and models of bass saxophones. They'd have the best information to compare horn A to horn B. I can, in general, say that the new horns from Benedikt Eppelsheim
are quite highly regarded -- there's enough eye-candy on his website to definitely qualify for this thread -- and I obviously point folks his way.
There are a lot of companies that currently make or have made bass saxophones, so you've got an awful lot of choices.