> I noticed ads for uncappers that used rotating brushes or chains to
> remove cappings. Anyone have any experience with them?
 
I use a Dakota Guness and it uses this chain principal, only the combs
travel down a conveyor belt through a tunnel which houses the chain flails,
rather than being lowered individually into the flail housing as in the
small chain units you are likely considering.
 
IMO, they all work just fine.
 
FWIW, up here in Alberta, a neighbour has altered the Cowen system -- with
Cowen's blessing, I gather -- to use chains rather than knives.  he has
sold quite a number.
 
Allen