Wolf Head or Vonnegut brush sander

[Mark Levitski]

Any one have experience with these? How long do the loads last? How easy is it to advance the abrasive? IT seems that they have been used for a long time in the commercial woodworking industries. We do a lot of spindle-type sanding for rustic furniture legs and need a better way. We have tried the epoxied together sanding mops and they don't last long enough for the expense. They have no brush backing.

Thanks.