George, be very careful getting anything from Estes. Thee have been some real quality issues raised on their products and I can assure you that they do not run as well as the origional Cox products. Their product line has been indeed discontinued by most of the major carriers but from what I was led to understand it was an availability issue. Estes pretty much desimated the old Cox plant and got rid of a lot of the equipment. They sold motors for a long time from the stockpile of parts that they had when they bought the company. That was I understand a huge pile of parts. It also explains the mix and match approch to tanks and cases as their parts supply dwindled. They sub contract their engine manufacture and a lot of the little steps like taper boring ,and holding really close tolerances seems to have been discarded in the process of cheapening the product to maximize profit.
Many of the product motors have crap in them and the ball socket fit is very loose requiring you to set them before you run them. Given this set of circumstances it is no wonder that the price of genuine Cox stuff especially the high performance parts has exploded on the bay.
Also gone are the competition props and most of the support equipment that they once made. Have you priced glow plugs for even the cheap motors. Oh and don't look for the competition hi compression plugs either. They believe in a one type for all, cheaper to manufacture,

And as a final note, most do not realize that from the moment that Cox was acquired by Estes they NEVER placed an add in any model magazine or made and product availability annouincement in any magazine. This company is not there to support the model community in any manner. This company has concentrated it's approach solely to the TOY market, namely plastic and foam RTF at your local Wal Mart. That said I'd rather not support them at any price.