I've honestly never met a gunsmith who didn't knock CGs. I remember my smith sticking his nose in the air and saying: "When you get a problem with the ejectors, AND YOU WILL, don't bring it to me"!
Well he died a coupe of years ago but my ejectors are still going strong and I've yet to see one have ejector problems. Why go to a gunsmith anyway when AngloItalian will always step up with a trained smith and access to the factory? The only problems I've personally seen are finger trouble issues with the 4 or 5 adjustments for the trigger pulls and the adjustable forend because some people just can't leave things alone.
Ask any sporting ref which makes of O/U suffer with most fail to fire and the answer is always Browning/Miroku by a wide margin and it's almost always the bottom barrel. OTOH I see a lot of CGs and have never yet witnessed a FTF that wasn't a faulty shell.
IDK whether or not my CG will last for half a million rounds but I really don't care because I'll be 75 in a few weeks and shoot about 4,000 shells per year.