This may be a case of "if you've gotta ask…"
What's your motivation for getting a folio? To use it like a wallet substitute? For a bit of extra screen protection?
A lot of folio cases work better in theory than in practice when used as wallets with cards in the cover slots. They prevent the flap from sitting flush with the screen, and just make the whole package bulkier in general.
The secondary microphone used for noise cancellation is part of the camera bump, so if the flap is folded over and conceals it, that function is negated. Obviously, that changes how the phone must be handled during picture taking, as well as in general.
OTOH, if a case has, like the Apple folio, properly implemented sleep/wake functionality, it can mimic an iPad with a Smart Cover. Having a front cover gives the screen a bit of extra protection, and it can be put into a pocket with some impunity.
That said, I do have a folio case, but not Apple's, which is nice, but whose asking price was too high to risk when I first considered a folio.*
I hedged, and got a cheaper folio from Amazon, which also has a detachable inner case. I don't use it as a wallet, and the biggest negative to me is the added bulk. The flap can be a bit of a bother in some situations, but then I just detach the phone from the rest.
Otherwise, the balance works out fine for me. I used to use a sleeve, and don't mind the overall package which is tidy, and covers the screen. I like full protection, and the sleeve was a bigger hassle to deal with.
The only real way to tell is to try it yourself.
*Best Buy has the black and red Apple Folios on sale for Labor Day. I could have sworn it was half off for the black, but it shows $58 now. BB isn't afraid to adjust pricing during a sale. You could probably get the Apple Store to match, maybe even with another color. They both have two week return periods.