Pros: Trim, well-fitting, holds up well, easy to use
Cons: Binding stains
The only conceivable downside I can think of is that the binding stains, but that's not unexpected for any cover. I haven't even tried to sun them yet, though I expect it would help. Of course, the more we've been folding our PFs and snappi'ing them, the less of an issue that has been - and it was a minor one to begin with!