Sounds like you are falling victim to the Internet Amplification Effect. One or two unhappy customers get 99% of the coverage while the rest that don't have issues just happily go on shooting with their gear. People that aren't experiencing problems aren't going to start a thread that goes something like "My Phase One XF or my Leica S2 is great and just keeps on clicking..." but somebody who is having a problem is likely to post something to either get help or to get their frustration off their chest. The internet amplifies issues drastically due to this.
Brand/Product reliability is even more difficult to evaluate than you've described.
Even with very unreliable products the majority of users have few or no problems. Among any reputable brand it's the overwhelming majority. So we're inherently dealing with low-probability events when we talk about the failure/trouble rate of any manufacturer. Human intuition does not do well with gut-feeling-evaluating low probability events. And the internet, for a couple reasons, makes it harder, not easier.
On a forum, if all else is equal, the brand that is most frequently owned will have proportionally more complaints aired. If one brand has, for example, 80% of the total users on a forum, and that brand is twice as reliable, it would still have twice as many problems reported. There is even a bit of a feedback loop; generally speaking more reliable equipment tends to rise in market share over time.
So it can often be that the most-reliable brand has highest number of problems reported.
That's can be true for cameras, TVs, video game consoles, bikes, mowers or anything else you can buy. Of course the opposite can also be true (that the one with the most complaints is the brand with the most unreliable product). The point is you can't tell all that much from the total number of problem-reports.
As one example, it would be very hard to find
any complaints about Megavision digital backs on this forum, but the number of Megavision users here is probably a handful or fewer. I am
not implying anything about the quality and reliability of Megavision backs in saying this; to the contrary my point is that you cannot imply
anything (positive or negative) about Megavision reliability/quality given how few owners there on the forum.
There are three places I think you can derive a very good sense of probability-of-issues.
1)
Dealers with years of experience
2)
The manufacturers themselves, all of whom (that I've worked with) keep detailed logs of repair and failure rates
3)
Rental houses and digital techs who have years of broad experience
With (1) you need to be aware of bias (for example I feel I have a very good real world feel for failure rates among major medium format brands, but I know I'm biased even if I'm actively trying to fight that bias to provide our customers fact-based advice).
With (2) you're unlikely to ever see these numbers in public. Even if your rates of repairs are an industry low it's generally felt to be poor "messaging" to focus people's attention on a statement like "Only 3 in 100 of our product require repair during the first three years". It would be like a hospital messaging "At our hospital you're moderately less likely to die from a mistake we make". While this kind of blunt-truth style of presentation/marketing fits my personality, there are very few corporate advertising departments that would agree.
That leaves (3) which I think is your best bet. A well experienced high end rental house or digital tech who deals with multiple brands over many years will have experience with many copies of every component (multiple samples of any given lens, back, body, many version releases of software) and also has the expertise to know the difference between user error and equipment failure and the mentality of doing reasonable things to make things work. Their experience will tell you that no brand is without some rate of failure/problems but there is significant variation among the brands on what that rate is. Talk to a few for even better results.
But of course, with anything that is probabilistic the results for any given person are only likely to follow the overall trend, and there can be very high variation within the population of total users. I once had a customer who had three
separate and unrelated components fail the same week, all of which (from broad experience) I would normally tell someone were very high in reliability; that should be a one in a thousand kind of chance, but if you have a couple thousand customers it would be stranger if that didn't happen to at least one customer than if it did. Trust me when I say that it doesn't matter much to someone who has several major issues, whether they are a 1/100 or 1/10,000 situation; they are (rightfully and understandably) more concerned with the numerator (the "1" that was affected) than the denominator (all the people who didn't have problems.
From that point of view, how the dealer (and manufacturer when relevant) responds to the "1" is just as important, or maybe even more important, than the exact probability of a problem happening. For example, I'd rather have a 5% chance of a problem that was quickly and painlessly resolved than a 1% chance of a similar problem that took days of hassle and lots of mental energy and stress. I'd rather be a blade of grass on a course where a dozen light whiffle balls were being hit than a blade of grass where a single golf ball was being hit.
Even worse, many products have a significant break-in curve. That is, the first few days, weeks, or months it is available it has far far more problems than after that period. For example if you judged iOS versions based on the first X.0 release you'd say Apple puts out
horridly unreliable phone operating systems. If you judged iOS based on the release available two months after the initial launch you'd say that, of course there are a few bugs for some users, but generally Apple phone operating systems are rock solid.
Excuse all the golf analogies. I'm really not much of a golfer. But it's so cold and harshly windy here in NYC that I'm dreaming of some place with sun and a gentle breeze.
