I’ve got a Bootzipper. I really like it so far (had it about 3 weeks, have ridden it about 100 miles off-road so far). Decided to get it after realising that a gravel bike wasn’t for me. Think the Bootzipper falls nicely into the niche between gravel and ‘proper’ MTB. Plan to use it for getting out and about off road close to home, and bike packing.
Re. the brakes and gears, it’s bottom of the range stuff but has worked fine so far. The gear range is basically the same as I had with 2*10 on my old MTB, and I’m not missing the in-between gears yet. The brakes work fine for what I’ve used the bike for. They squeal like anything in the wet, but suspect that might be more down to me not bedding the pads in properly, and having to ford a couple of streams recently.
It’s not light (but then you wouldn’t expect it to be), and it does feel like it takes a while to get up to speed (but then I’m comparing it to my 26 inch wheels MTB and road bikes, so I’m probably not the best judge).
Basically I’m enjoying it a lot, but it is just what I expected for the money. (Have already changed the tyres and saddle, and added a dropper though, which adds a bit to overall price)