Can I use a "BL" Blacklight for a party?

In my research for buying blacklights to light a "highlighter party", i came across 2 types of blacklights on the market. Blacklight (BL), and blacklight blue (BLB), where the BLB actually appears black when off, and the BL simply looks like a standard fluorescent when off. I've found the BL to be about half the price of the BLB and therefore want to know if there is a significant difference between the perceived effects of these two blubs.