No... you both kind of missed my point. I have a complete set for MAME 0.139u1 and I used ClrMAMEPro to confirm the validity of the ROMs. That's not the issue.
The issue is that the set is 26 GB, and of that 26, at least 6GB (at a minumum, probably more) are classified as non-working ROMs. As in, MAME supports them, and will load the game, but the emulation is incomplete, and you can't actually play them. So perhaps the correct term is incomplete emulation ROMs.
In a day and age of 500GB, 1TB, and 2TB drives, 6GB is not an issue, and I'd just live with them. But we're talking about a 32GB SD card that I'd like to make the most use of, and put other system's ROMs on. 6GB of wasted space is not exactly ideal. I was manually able to whittle the list down to 20 GB by eliminating the largest ROMs, but I'm sure there are further incomplete emulation ROMs that I could remove to get the directory even smaller.
So what I'm asking is, is there any utility that can filter out incomplete emulation ROMs?