But I would also be very interested in any additional benefits, such as if they make gun-show purchases any easier...
They might, they might not. Depends on the dealer themselves. Some, even when presented with a copy of your FFL, will still demand that you fill out a 4473 and go through the NICS check (effectively treating the transaction as a "normal" one, ignoring your FFL). This can be ignorance on their part (not knowing it isn't needed) or just malice (not every 01 FFL likes us 03 holders, they'd prefer we pay their markup and profit rather than get the same deals they do).
Either way, you're still best off buying directly from distributors. That's where the gun show dealers and retail shops get their guns. You can pay the same price (say, $80 for a Mosin Nagant instead of $130-150 at a retail store) that they do, and you don't need to cover anybody's overhead.