All Tony's stuff is legit, i know where a lot of it has come from.
There was speculation that his stuff is shill bid, but he's been buying and selling nice stuff for so long he's simply got a load of saved watchers both here and abroad that are prepared to pay that bit more as they know they're getting quality or legit parts.
Obviously theres still those that don't set their limit and get into bidding wars - he does well at attracting those Wallys...