//gainsborough wrote: ↑
From what I've gathered, avant prime boards are basically a lesser quality northgate omnikey. The couple that I've seen torn down have had their mounting plates glued to their PCBs, making it impossible to do any kind of plate restoration. It also (I think) exclusively comes with simplified alps. You should be able to do a switch transplant in one, though. Even though the plate is attached to the PCB, you can still desolder switches and replace them with something better.
In any case, $185 is pretty steep, even for an omnikey. Can an avant prime be fully reprogrammed?
I believe you've gathered correctly.
The Avant Prime was the successor to the Northgate Omnikey 101, but with a few important differences. But a disclaimer first, because we can not assume that all Avant keyboards were the same, any more than we can assume that all Northgate Omnikey keyboards were the same.
The switches were indeed simplified Alps, at least in all the examples I've seen. The Avant keycaps were usually pad printed with a clear coat, rather than the double shots that came on the Northgates. That's visible in the closeups on this one, but it's interesting that this example has neatly done clear coating, rather than the looks-like-hand-painted blobs seen on some Avants. The layout is also different than the Omnikey 101, most notably the Avant having a BAE rather than an ANSI enter key. (Some late Omnikeys had a BAE and windows keys also...) The LED window on the up-arrow key (and non-clicky switch there) indicates this is a programmable model. I believe all Avants (and a few late Omnikeys) came that way. I don't know if the Avants are subject to the same programming chip failure as the late Northgates. My Avant Stellar still has its original programming instruction sticker across the top. I can take a photo of that if it would help anyone.