I'm really interested in the the NV610 and the NV215. I've heard a few remarks on here that the bergantino's need a lot of power. I need a very efficient cab for my v-4b and it's 100 tube watts to keep up with the rest of my band. Will the berg's be loud enough with their great tone, or should I look into something more efficient? .... and do you recommend the NV610 or the 215 to match with my head? There is just something I love about the 215's.