I've been repairing mowers for almost 50 years...the last 20 years ive been using the aftermarket chinese carbs for briggs...either the nikki or walbro style with maybe 2 issues over 200 carbs...OEM gets 4 markups before its sold to you...briggs buys almost all ov their carbs in china now...the markups go this way...briggs arranges to buy a lot of carbs for distribution...they add a markup on top of the buying from the OEM...then sell it to the distributors who mark it up for sale to the dealers who mark it up for sale to you...4 markup from the original suppliers...ill keep buying the aftermarket and save my customers a lot of money...
There is a big difference between an aftermarket carb from a reputable supplier and the cheapest one you can find on ebay or amazon.
I have never fitted an original carb to an engine for the entire time I have been running the business
I do fit aftermarket carbs from my wholesalers and have never had the slightest problem with any of them
I have also bought carbs directly from the factory / distributers in China and never had a problem with any of them other than having to dispose of the excess when I had to order 100 . Thi is not don for a cheaper price but because the wholesalers do not stock every old carb .
OTOH I get 2 to 3 customers through my gate every month who bought the cheapest carb off ebay then found out why it was so cheap .
I had one customer who bought 3 of them from 3 "different" vendors thus spent more than a certified carb from me .
I suggested that they were all probably sold by the same person using different names .
HE checked his pay pal account & found that yes 2 of the payments went to the same account despite one carb being less cheap than the other .