I'm running it on a 256GB Silver Wi-Fi only model (iPad11,1). It's not any more sluggish than iPadOS 16 was on the same device. However, my experience with it has been that it's royally glitchy. It won't consistently sync my music from my MacBook Pro (13-inch, M1, 2020) running macOS Sonoma. I had to replace it once for that already (the replacement unit cooperates much more consistently in this regard, but it's still nowhere near as smooth as on my other devices). I've done multiple DFU restores on my 5th Generation mini and even the setup assistant has odd glitches and doesn't behave consistently from one wipe to the next (sometimes it'll prompt me to set up "Hey Siri", some times it won't). It'll tell me that I've changed my passcode since the last time I invoked TouchID when it doesn't get my fingerprint in correctly (nevermind the fact that this is completely erroneous). A lot of glitchy behavior that I probably wouldn't have noticed had I not needed to do multiple DFU wipes to figure out why it wasn't consistently syncing my music. But still plenty of it thereafter. And again, this is across multiple 256GB Silver iPad mini (5th Generation; Wi-Fi Only) models.
I don't know if this is unique to iPad11,1 units, 256GB models, Silver models, or Apple replacement units (my original one was an Apple Certified Refurb unit, the second one was a Genius Bar replacement unit which is, more or less the same damn thing).
What I can say is that I have iOS 17 on my iPhone 13 and have zero problems (at least, zero problems that haven't been in iOS for several major releases already). I have iPadOS 17 on my iPad Pro 12.9-inch (3rd Generation, Wi-Fi Only) and it's mostly okay. A far cry from the glitchy mess that is iPadOS 17 on my iPad mini (5th Generation, Wi-Fi Only).
I actually came across this thread on my way to searching whether or not I'm unique in this regard or if others have similar mileage on such an iPad mini.
It really blows as Apple is completely clueless about whatever it may be that's going on with my iPad mini 5. I'm hopeful that iPadOS 18 completely resolves my issues as this would be an extremely lame note to end my use with what is otherwise a pretty decent model of iPad mini.