I've just received the wheels I ordered on May 26.
It was shipped on April 2nd to the EU so all-in-all standard times. They took a bit longer to ship because they had to be built. It was properly communicated so all good.
They have the standard rim, and weight with caps, valve and tape is 1490g which should bring it down to the announced 1465g without tape, valve and caps.
The hub sound is OK. Not too loud (thank god) especially compared to the elite wheels elite one I have on mine - which I hate).
It came with some nice gifts, though as mentioned I it would be nice to inclide 2 extra spokes too.
For 319€, delivered home, without custom duties. Seems fairly unbeatable.
They will be used to build the super budget bike for a client. A full carbon bike, hydraulic 11s, integrated cable for under 999€. All with new parts.
Full build will take a while, but will do a 6months review to keep you guys updated when the client comes for maintenance -after summer.
So far, Matter and his company have mu highly recommend stamp and will become my wheel supplier if all goes well.