Has the car already got a cone filter as part of the standard set-up?
Usual question is aftermarket panel filter vs induction kit - first one just replaces standard filter, supposed to flow air a bit better and may give a bit more induction noise.
Induction kit will usually be cone type filter plus various pipework which replaces the standard airbox. Open filter systems give fair increase in induction noise whereas those which have the filter in an enclosed canister tend to be quieter.
Performance increases depend on the standard/design of the kit, what car it's going on and what other modifications the car has had. Just because it sounds better doesn't always mean it's any faster, and in some cases the car can run worse or need other changes to get the full benefit.
Have usually run K&N kits on most of my cars, my current kit is a one-off variation I did to their original kit taking advantage of extra know-how gained as the model had been out and about for a few years after K&N launched their original kit.