I've used Plano Pawn and Tom Hart. Both are very good. Since Tom's closer to me and offers the CHL discount, I use him mostly, but I'd use Plano Pawn again without hesitation. One caveat: Plano Pawn will only accept shipments from other FFL holders, not private citizens. Tom will take transfers from private citizens if they include a copy of their driver's license.
NRA Endowment & DSC Lifer