I recently placed an order with B&H. Among other things, I ordered an 8x10 Unic olor drum. The guy asked me if I wanted the $50 film drum or the $15 drum. I w ent for the $15, but told him I wanted the one with ridges inside. It came toda y. It is white with a smaller black tube sticking out. Inside it is completely smooth. Should I have purchased the $50 drum? Are there different types of Un icolor drums?

Thanks, Dave