MF,
I don't do much with the Briggs these days, just the odd one here and there and surprisingly I have only had one Chonda with a leg out of bed, and I know where it came from and it had been abused big time, flogged into the ground and run out of oil. The Chonda motors (cranks and barrel/piston) don't seem too bad , it is just all the ad ons that are rubbish (carbies, governor setup, pull starts) that is what lets them all down