Yeah, the volume boost is unavoidable - on dry mode, if you have the volume all the way down, you just get a clean sound at normal volume. Any increase on the volume knob from there adds fuzz volume on top.
I use my BBM on dry mode with the volume around 2 o'clock to get the wet/dry ratio to my liking, then turn down the master volume control I added with a simple mod: [url="http://basschat.co.uk/topic/112212-bass-big-muff-volume-and-feedback-mods/"]http://basschat.co.uk/topic/112212-bass-big-muff-volume-and-feedback-mods/[/url]
Definitely get it if you've never played one before, they are inexpensive and easy to sell if you decide to move it on!