The one I went for was the
AB350M Pro4 - it was on offer when I picked it up @ ~ £65, and I went for it because it was the cheapest mATX with 4 RAM slots (although the inclusion of USB-C was a factor too).
It's only been in use for a week, so it's hard to give a good impression, but in terms of quality, ease of build, and intuitive UEFI I've got no complaints. I splashed out a bit so it's hosting a 1300X, 16GB of the HyperX 2666MHz, and a 240GB NVMe SSD (plus his existing RX 460). AFAICT he spent the entire long weekend over new year playing on it, though, and he's promised to contact me immediately if he has any problems, so I'd guess it's holding up OK
And it had no problems at all booting the procesor and RAM with the shipping BIOS, although pretty much the first thing I did once the build was complete was update it to the latest one anyway!