Are production yachts generally more reliable?

Who perceives the lack of reliability? You?

Production vs. Custom isn't a clear advantage to either as so many players in each side. You look at the top of the line custom like Feadship, Lurssen and others and quality is excellent. You look at the small custom builders, really just brokers who find a yard to build the boat and quality may not be very good.

Same with Production. First, let's distinguish too that there are two type builders who fit this category. There are semi-custom where the structure is the same but lots of flexibility on the interior. As to 100% production where all you get to choose are colors than a few of those, but primarily smaller sizes. As they get bigger they give more flexibility. Our Riva's are 100% production. We bought what was at the dock. Westport's quality is beyond reproach (obvious bias as owner). There are others who range from good to excellent. Ferretti (including Riva and Pershing), Sanlorenzo, Sunseeker are just three with good reputations. Then there are many others who have a litany of buyer issues and complaints.

It's really not custom vs. semi-custom vs. production in terms of quality. It is builder vs. builder. There are excellent builders in all types and bad builders in all as well.

All depends on which anchor is on it.

I am not sure how you can really separate Custom/Production by builder because the builders with proven reputations pick their product and stay with it. . And semi- custom is still production, just a fancy name for pick your soft goods, even production builders do a good job of that game.

Westport only builds Production, Feadship only builds Custom, their products fit there business models and workforce.

You have to also factor your own taste - do you mind a yacht that is replicated many times over, especially from an exterior perspective, or do you want something to stand apart and be a more personal statement?

The Aero Industry is a difficult comparison for the Yacht industry.

They are much more regulated, much more definition on what can be used and what can not, and much more mandated/defined maintenance schedules, etc. There is more investment on many levels in that industry.

Even with all the classification societies, the Yacht Industry is far less regulated, which is a good thing in my perspective as it provides the end user more choices. But the mantra is buyer beware - proven and reliable goes a long way in many people's books.

Premium builder with outstanding references will help alleviate risk as well as proven Series production builder with all the bugs worked out and great references. Where is the warranty work done, how is it supported, as something is bound to need some attention at some point?

It comes back to your yachting personality - stand apart or part of the flock? Safety in numbers or trail blazer?

Of course the one off has a greater chance of not being as good as hoped. That greater risk is minimized by the right builder. Westport is going to perform the same as the previous 50 of the model.

There are many good reasons Westports are so popular. Custom builders, good ones anyways, can achieve a better boat than Westport, and a better ride persay, but then you never know exactly what you're going to get in regards to ride/performance as it is a one off boat, however many advantages of it being built just for that owner. A Westport does not hold a candle to a Feadship, especially behind the scenes (storage lockers, area's owners don't see, etc.). But a Westport is a very good boat and you know it's going to perform just like the last 30.

One other advantage of Westport is you can go charter the boat you're interest in.

A Westport sounds like a great fit for your purposes, enjoy the process

You mean the "Vango"? The 49m vessel with 2.3m draft. https://www.yachtforums.com/review/westports-new-164-vango.5319/
My last tug was 38m with 3.84m draft. The 22m gulet we are finishing up has 3m draft

Yes, 7'6" is a fairly shallow draft for a 164' boat but still there are places it would be restrictive.