I agree. The main reason for not buying a HS621 is its age. I already have a nice and one year old 2-stage Honda so I don't need another powerful blower. I don't care for buying an used one since it is really hard to know what the previous owners did (it is very rare that you find an original owner selling HS621). Sometime 1-2 year HS520 is not that much cheaper so why buy an used one with worned out peddles and scraper when you can buy a new one HS520 for $100-$150 more. I get the GC vs. GX but for a simpleton like me I am not going to notice any difference. The only reason why I replaced my 10 year old Honda lawnmower because I hit a tree stump. I had no issue with the GC160 engine and was trouble free until I hit the stump. It started and ran fine except for really heavy vibration. My new Honda mower has a GC engine and I expect that it will last for 10-15 years without any issues.
