I can’t say that I’ve seen too many of those negative reviews, but for each of them, I bet you can find at least a dozen positive ones.
As for my own experience, all I can say is that I have owned a Vertigo for 9 years, and it has seen quite a bit of use. It still looks new, and has had zero issues in that time. I also own several other products from Mono, which have all been of excellent quality, with a single exception. I did have an M80 bag which developed a slight cosmetic issue after 5 years of use, and Mono replaced that promptly, in spite of the fact that the issue did not in any way compromise the utility of the bag, and despite my having lost the original receipt. Mono stand behind their product, and their customer service is second to none.
More importantly, Mono bags have kept my basses and other equipment safe for nearly a decade, without a single scratch or ding, and I’d happily stack them up against anything else on the market.
However, we must all find happiness the best way we can, so I wish you luck in your search, whether you end up with a Reunion Blues (which I’m sure are great, by the way) or something else.