CE Roth in Allentown is a great local shop that does first class work for any formal rentals. I have been to them for multiple weddings and they have been great every time.
Their prices are usually significantly cheaper than the national shops for pretty much the same thing. They are only one shop and local to the valley, so the only hard thing is if you have groomsmen that are from out of town, but they can get measured locally and send the information to the shop.
PROS: good prices and service
CONS: only one shop
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