@agowa338
I like it and have used it for years. I like the ability to use mismatched disk sizes, I can store what I choose on whatever disk, or let it spread data across disks. I like that if I have a failed disk, I can move stuff around and remove the failed disk without having to go buy another disk, then slap in a new one later, if I want.

In general, performance isn't great. Reading is same as 1 normal disk, but writing is slower. This is because the parity needs to be updated in real time. That means either (a) reading the data on the disk before writing over it, or (b) reading the data on that spot on all other disks. Caching writes to an SSD (ideally mirror), and having them later move to the array is a common and recommended setup.

The one pitfall I'd point out is very poor write IO in a failed disk scenario. Unraid will emulate the failed disk, so it appears accessible like normal for read and write. Every time you read a file on the failed disk, it reads that spot on all other disks and the parity disk to reconstruct what data was on the failed disk. If you want to move that data to a different disk, it needs to use all disks to reconstruct the data, then normal "read before writing" + actual write on the other disk + parity update. That is a lot of reading, and it slows everything down. It works, and I've needed it several times, but the recovery feels so slow.