It seems the B9 is a tad more expensive and also requires self assembly. I'm not sure why but their site is also incredibly slow and a pain to use in some cases

It seems the B9 is a tad more expensive and also requires self assembly. I'm not sure why but their site is also incredibly slow and a pain to use in some cases. With that said it does appear to have a higher resolution in the Z plane than the Form 1.