I'll pull in my reply to this from the HammerBowling.com forums.
Hmm.. Question: how are sales of the spare balls going? I mean, the only options currently available without going overseas are the Taboo Spare and True Blood. Perhaps another one in the works with the Dead Center Core?
Or how about a stronger urethane piece? Good strong urethane cover, First Blood, Powershot, or Fatmax core? I don't know if the Vibe core did the New Blue Hammer justice, as people may have just simply seen it as a urethane Vibe.
BL.