The rims are very similar to the ones I plan to use on the FM936.
The AM927 of lightbicycle.
A bit less depth of 24mm.
And they offer a 10% lighter version than normal at ~360g
I do not build wheels anymore.
Getting the rim, saving a bit of shipping cost by ordering home the hubs, spokes and nipples cost the same. And I have still to build the wheels.
What I keep doing, is to check the tension is perfectly even on all spokes, by ear.
In general it is fine, but sometimes it needs a bit of tuning.