I have a difficult to fit horse. I could not find anything that fit my mare (or me, but I would have bought something that only fit her but not me). I tried other people’s saddles, used saddles, and new saddles. Nothing worked and the saddles often left raised skin/welts/ridges.
Devoucoux worked with me and I sent it back at least 4 times to get the panels redone at their cost with no hassle. The rep (and then her manager) came in person a couple of times. I took pictures and emailed them to the saddle maker. It did take a long time. However, they also gave me an almost new loaner to use, which worked with a Beval pad. In the end I gave up on the custom fit and kept the loaner. It fit me well and worked well for my horse. And, I had no options in the alternative. (I rode her in a western saddle for the first year and bareback was not doable.) Sure, I wish that I could have had a custom saddle that fit like a glove, but I am happy with what I have and happy with the service.
I can’t really comment on other brands. I know someone with a Voltaire and she’s happy, and one with a Trilogy, also happy. It’s always a good idea to shop around and see what fits you, not just your horse.