I converted my Surface Tek two years ago with a Tll and have put many skids of glass and olivine through it. Lately it has been hit or miss and so I opened it up and it's all buggered up in there. Re build kit is almost as much as new so I just ordered a new one. Have to say not a speck of wear on the tungsten sleeve. Just every other metal part in it. This time around I ordered extra red doughnuts. Maybe could have gone longer. $400. bucks a year on wear parts isn't too much to ask I guess.