I have a B22, a DII & a D2. The DII is the same as the D2, only an earlier model and has a condenser. Isn't that what the B22 is? A condenser? I have been using the D2 because it has the color head / diffuser light source. I can just dial in the filters on it. I can't be sure, but I think the B22 had a filter holder underneath the lens. This makes a difference. Also, with the D2, you can take a 35mm negative and enlarge it a lot more or crop it a lot more.
I guess it depends on what kind of light source, what kind of filtering, and how big of an enlargement you want.
Good luck! It's a GREAT piece of equipment, even if it's old.