No matter how good your band saw is, if it doesn’t cut square it’s not living up to its potential. Usually setting a band saw blade square to the table involves a lot of cutting and checking of scrap stock — or you could clip this blade alignment gauge to the blade and check the alignment easily with a machinist square.
MSC sells the Starrett version for $54 (up from $27 in the 2006 catalog) and the Lenox version for $6. I own the Starrett, and it works great, but I doubt it’s nine times better than the Lenox version. If you work with a band saw, there’s no reason not to have the Lenox, especially for $6.