When it's maxed out in Generations, with the right skills, it can kill monsters pretty easily. As this poor Ukanlos found out.
Mind you, Ukanlos is an Elder Dragon-level monster, and according to Kiranico, the one in that quest has 10990 HP.
But yes, Blast/Slime was extremely broken in 3U. For GenU, the Teostra bow got nerfed because it was so strong.
I usually main CB, though I also run with GS and Hammer, and I love using Bow and LBG in Generations with the Aerial Style. It's flashy and impractical most of the time, but it makes mounting easier.