I agree that Daniel Beringer is to be congratulated on his efforts to supply what the astronomical community needs. I have bought a few different items from Frontier Optics in recent times, most recently with a 12mm HD ortho, and have been very pleased with Daniel's efforts.
BTW, I notice he has on his site the Williams Optics Crayford Focuser for SCT for the bargain price of $250. That is a great deal.....if you have an SCT and find mirror shift irritating, this item will be money very well spent.