I'll preface this with the fact that I do consider Bill Schwab a friend, but I also believe friends need to be truly and sometimes bluntly honest with each other.

Mr. Schwab has hit a F'in homerun with these holders. I was honored to get one of the first holders to test out.
I spent the entirety of today out shooting with the North Light wet plate holders. Completely flawless.
I made about 6 collodion plates on aluminum and 2 plates on black glass.

The holders is extremely well made and the design is executed impeccably to function specifically for wet plate, and function well.
Lots of nice little touches. Theres a "frame" edge all the way around where the aluminum/glass sits inside the holder. This edges works well to keep any residual silver from seeping into the darkslide slot or other areas. The edge is made form a white plastic material so is easy to see even in a dimly lit darkbox. This was really handy when placing the aluminum plate into the right place as the white material made seeing it a breeze. This might seem miniscule, but its a nice touch as often youll get collodion tears if the al/glass plate moves any inside the holder.
I'm accustomed to using a holder with corners as opposed to an 1/8" edge all the way around. I found the 1/8" edge nice because the plate sits securely in the holder and doesnt move in the least.
The holder is about as light tight as is possible. I was out shooting in bright sunlight and moved it around in every possible direction and got clean plates every time.
The retaining clasps that hold the back closed were easy to work and the pressure spring was plenty tight to create enough pressure to keep the plane of focus spot on. The 8x10 creates a plate that is 7.75" x 9.75" I was using aluminum and glass that I'd cut for my older holder that was 7.75x9.5 so my plates didn't fill the entire holder but this caused no issues as the backing glass helped to hold the plate in place. You'll notice the lack of black border on the bottom edge in the below triptych.
The holder slides into my 8x10 and locks into place perfectly, no moving around and absolutely no issues with light leaks or incomplete "seating" in the back. Another notch on the "well designed" belt.

Bill has really done a knock out job. I've been using a modified older wooden 8x10 holder and this is night and day better. Don't have to fumble around with two dark slides, bent plastic as a "pressure spring", darkslide rubbing against the plate...

Highly recommended. If you want to get out and create plates and want a good quality holder. You can't go wrong, especially at this price.