SD Chamber and barrel do need quite a bit of work to get them working smoothly. Chamfer all the lugs on barrel and the slide if you can with a needle file. The slide wear unfortunetely is normal. I think its a design flaw on the manufacturer's part. I have the same issue with my Infinity slide(as does ILLusion), prolong use will cause the slide to be useless, since the outer barrel cannot be pushed by the moving slide to return to battery. I have fortunetely negated that problem when I converted my slide to a hybrid layout, but with regular barrel I don't know what can you do to fix it permanantly...maybe other attachment such as a compensator might help...
I know that on Nova's 1911 slide and SD's Hi-Capa slide no such problem exist since that particular area of the slide was made beefier than the Airsoft Surgeon's. There is a new batch of slide ordered by Illusion from the same manufacturer with some custom geometry to try to prevent this from happening, but I don't know if the manufacturer themselves are addressing this issue on their future run....