I received my G028 yesterday, and have started to inspect / build it up.
The QC was reasonable: the BB and brake mounts were faced adequately, the headset bearing interfaces and fork were clean.

There are two issues I've found so far:

• The seatpost clamp wouldn't fit due to paint overspray and some excess resin. Without the seatpost clamp, a 27.2mm seatpost fit just fine, but as soon as the (fully expanded) clamp was installed, it was too tight to fit a seatpost. I removed a small amount of material with a dremel, and it's now a perfect fit.
• There are several small paint defects, from a hasty paintjob. These are fairly minor and for the price I paid I'll be able to live with them.

Frame and Fork Weight
My frame is painted in green metallic, and is a size large. The frame weighs 1271g with no accessories/hardware, and the fork weight 502g with an uncut steerer.

Chainring clearance for road cranksets
I've fitted a SRAM Force D2 road crankset (standard road / non wide) with a 44T chainring (with a 3mm offset, rather than the standard 6mm), and with a 2mm spacer there's plenty of clearance to the frame (±6mm).

I'll be building up with SRAM Force E1 shifters, SRAM Rival E1 XPLR 13-speed rear mech and SRAM Rival XPLR 13-speed 10-46 Cassette, and various components sourced from AliExpress (seatpost, saddle, stem, bars). I have a carbon wheelset from CSC, 32mm internal, 41mm external, 50mm deep, 54T Star Ratchet, steel spokes, 1450g.

I'm expecting a final build weight to be ±8.75kg, and will post pictures when it's complete.