I had wondered about the kits rose326 sells myself, they're priced good for sure.
The particular x80 kit I was point this person to is one of the PK-80 kits that has larger tranfer ports in the cylinder and. The longer bent clutch arm, mine also had the one piece crankshaft that has the balance holes drilled in it, may not be a bit better or even as good as the kits from rose326 and if you have bought that many from them and never had a lemon I'dsay thats a dang good track record for sure.....
Map
Yeah, honestly I started buying from them when I got a single outstanding engine the first time. It had the red insert clutch lever and ran like a champ from day one.This engine lasted me over 10k miles without giving me a single problem! I never needed to pull the engine apart, so I never did look inside the cases to see what was different, but it was the single best ht I ever saw. I recently sold the bike it is on and it's still running strong.
I've heard something about rico group motors being exceptional and I'm pretty sure this was one of them. I have never since seen the red insert clutch lever but I would love to find more of these kits to see if it was just chance.
The kits I now get all have been good running and durable as far as I know. I have never yet had one of my buyers call back with a major engine issue, so I assume they all still run. The only issue I ever had was one early kit came with a bad coil winding which was replaced free and fast.
All china kits are something of a cr-pshoot, but I like knowing the vendor stands behind his engine kits. I highly recommend these (this)vendors based on buying many, many kits problem free.
(Your results may vary)