i bought these as road wheels for my 2018 Giant TCX w front and rear 12mm thru axles. When I swap out the stock wheels for either my Stan's Iron Cross or Grail, all wheel sets drop right in and I think I barely had to tweak the rotors once and I don't have to adjust the shifting between the rear wheels.
But for the Mercury, the 12mm front TA wouldn't go through. Well that's weird. Turns out the 12mm hub adapters for the Giant stock wheels and Stan's have an OD of 19mm, but the Mercury 12mm adapters have an OD of 21mm (measured w digital caliper). That 2mm is enough so when the hub seats in the fork, the axle hole is off center with the holes in the fork and the TA won't go in.
On the back, when I first put in the wheel, right off the bat it's clear the disc brake rotor will need a spacer, and the shifting is off. Neither of these issues are unusual swapping different rear wheels or hubs, but there it is.
I emailed Mercury and didn't get a reply which is disappointing.
But as others have suggested, these wheels hit a sweet spot between price and quality, so I'm going to have the front adapters machined, space the rear rotor, and deal with the shifting.