I received this email from John Locke, aka "Rusty Nuts", a long-time friend of the NTC:

Last year I bought 20 rims from one of my distributors. I discovered that the valve stem hole was on the LOOP side of the rim.
This is totally wrong, and makes it next to impossible to install either the tire tube valve stem and / or putting the center section back in or remove it. (see images)
I complained to my vendor, and they recognized the problem and took them back.

Now I see they are offered on Amazon and eBay for very reasonable prices.

I checked with my other vendors and only found one that had the correct valve stem location (opposite side from the loops). So I am thinking the manufacturer of the rims made a run of these rims that were assembled incorrectly. Yes, there are a couple size loop rims that do have the valve stem on the loop side but NOT the 9 x 28 or the 10 x 28. The image clearly shows how close the valve stem is to where the center section fits.
What some will say is put the center section behind the loop. Well that will look like crap and it puts the offset out. Buyer beware.

Below is an image of the CORRECT valve stem placement and the WRONG valve stem placement.
Thought maybe you could run this somewhere in the N Club forum ASAP.

With the valve stem that close to the placement of the loops, means you can only put the hat rim on one side, limiting the rear tire width options. They're still usable, but still incorrect.