BTDT! I went through 4 SW temp gauges before I got one that worked, These came from a big truck parts dealer that sells a lot of parts. I will agree that there are aftermarket parts that are better than OEM and some that are just junk! Its a crap shoot buying them. Its kinda like this, To say the aftermarket industry is all bad and junk stuff is wrong.
Just think about how many aftermarket parts you really use without thinking about it. How many of you out there have gone to NAPA or other parts places when the starter or water pump goes out of the tractor? Do you go to the dealer to buy ALL the oils and filters for your equipment and trusty old pick up? Did you buy that tune up for the Oliver 88 from AGCO? When the back rims on the old 4020 went bad did you go to JD to get factory replacements? I could go on and on. If you don't buy it from the dealer then it aftermarket, Plain and simple.
So before you bad mouth aftermarket parts and call them all junk just think about All the parts and stuff you buy that you use every day that did not come from the OEM dealer. They all make good and they all make bad. Just something to think about. Bandit