Chainsaw Repair

Today i got some parts for my Redmax 621. Gasket  set[for a 62 cc China clone] and a carb isolator. The case gasket is a perfect fit, the isolator is a little diferent.Seems that the 62 cc clones are copied exactly, and the 72 cc clones are on bigger cases.

Which one is which in your pictures?  The one on the left looks like what I remember from my 62cc, but of course it is assembled now. 

Recently some versions of what is sold elsewhere as the Topsun T6220 came up on eBay here at a very good price, and with some better pictures.  They have clearly changed all the plastics, and the top cover design looks like an improvement.  I could not see the air filter arrangement but the G621 original could stand some improvement.  Also the high idle throttle lock button was gone, so I assume it must have a carb with a more conventional integrated high idle/choke linkage, which would also be an improvement. 

I'm curious about them and what other changes were made, but ironically the revised parts kept me from buying even if they are improvements.  There would be zero sources of spare parts here, whereas with my G621 clone I've got at least some chance of finding used Zenoah parts.