I ended up with 3 or 4 of the Girsan MC28 17 round magazines made by Mecgar. Found them in the bargain bin at a LGS and they were unboxed/unmarked but brand new. I was hoping they were for a different pistol.

I was going to flip them once a realized they were not what I was looking for. But then I realized the pistol can be had in the $250 range and has good online reviews. Not to mention Girsan is building a solid rep overall as well.

Anyone have any experience with them? I’m anticipating I’d probably need some grip tape for it. But it looks like it would make a great glovebox pistol.

So I’m on the fence between flipping the mags or just buying the pistol they go to. Not my first time doing that. LOL

But do I want to postpone other projects by $250 just to have another stash gun? Looks like I could get $30-$40 per mag so that would put me @$100 towards my projects.

They're fine.  They're overbuilt M&P clones

do they have magazine compatibility with another pistol?

CDNN => EAA GIRSAN MC28SA 9MM BLACK -- $239

As a former  owner  of the full size and the compact. PASS PASS PASS.
Sell the mags and keep walking.
I sold both of mine and do not regret it at all!
I purchased  both of mine on close out  for about $220 each.
Put the mag $ towards your next project!

Cz75