Have only used Silencershop, no problems. Individuals, no trusts. Recommend.
OP you may want to double check with your FFL in regards to fees. If they are a Silencershop affiliate I *believe* (could be wrong) there should be no fee when purchased thru silencershop directly. Least ways I've had zero transfer fees purchased that way.
When I bought one from a manufacturer directly, because silencershop didn't have them back in stock, there was a transfer fee. $50 IIRC. Bought the stamp from silencershop online, and they/my FFL did the e-form. Pretty smooth transaction. Would *likely* be the same/similar if my FFL had one in store & I bought it (transfer fee & smooth transaction).
Note: our FFL has a Silencershop kiosk, so that made it pretty easy to set up a Silencershop account.
No idea on if you do not have reasonably easy access to a kiosk, how that might affect things...
Edit, adding: Trusts, may flip ours over to one sometime in the future. Yah I know $200ea. + Trust $. Wanted them ASAP due to the supposed rapid individual approvals, so went that route. Were all pretty quick. Had/still have concerns over an administration "slowing things" back down again. YMMV.