I have purchased from Watsonr in the past and was always happy, and have been pleased in general with Meteor/Camber products for my customers' saws.
My aftermarket experiences as posted at the SH forum recently.
Most of my experience is with Huztl parts for pro model Stihl saws as I have used literally several thousand of them, second only in number to OEM Stihl.
Huztl stihl chain tensioners are less "smooth" than OEM. After installation, you need to work them back and forth with a big screwdriver to get the gears to mesh better.
Huztl MS290 recoil assembly (1 of three used so far I hate homeowner saws) had a sharp burr on the metal cord grommet and cut the cord on the third pull. They replaced it free.
Huztl MS660 (and many others, same part) clutch covers. In my most recent order of 30 covers, one package of 4 had paint problems. They are usable but not perfect enough to sell or use on a customers saw. They replaced for free.
Huztl MS660 complete engine, one arrived with a mangled oil seal, they offered to replace the entire part, but I declined as it was a 2 minute fix.
Huztl MS361 crankcase does not include the impulse hose nipple, just odd and about a $3.50 piece from Stihl.
Huztl stihl flywheels do not come with keys, $.99 from Stihl again just a little odd.
Huztl MS660 tank handle assembly (1 of 10) arrived with cosmetic shipping damage, ugly but usable, they replaced it free.
Huztl MS361 top cover shrouds (2 of 10) arrived with cracks, they replaced them free.
found a few more parts that are utterly shiiiiiiit from Huztl, I am sure they will replace but be aware
1. threaded nuts that are part of the air filter for an MS260 are soft and poorly threaded, two of the four I had on hand were unusable - they replaced
2. the tank vent on both MS260 tank handle assemblies I have are crap, they fail the pressure test after assembly and yanking the pull start a few times - they replaced the entire handle assemblies
Had an MS361 fuel line that I replaced for a customer online who said it split at the filter end after about 2 months of use with marine fuel (no ethanol).
Of the 650+ flippy caps I have bought and sold since July I had two of the small size that wouldn't seal properly.
DDave