I keep chain rolls and chain loops in stock with extra bars, clutch rims and drums. Buy on sale. If you do this for a living cutting costs is good. My two new saws 575/385 came with semi chisel skip chain. I never used semi chisel chain. Cutting at the saw mill with shoulder high tree trunks laying down the semi skip chisel chain impressed me. I just purchased a 100’ roll of semi chisel chain to stock up on it. The only difference I noticed was the cutting speed between the two different powerheads. The 385/32” has more muscle over the 575/28”. The biggest difference I notice is a dull chain on a 2100 will still cut not as fast as a good sharp chain but that last cut at the end of the day your happy it cut. Safety tip, do you ever check the wear and play in the rivets in the saw chain.? They do wear. A snapping, flying chain isn’t good.