I have the kicker 6-pack and previously had the 4 speaker setup. Yeah, the 6-pack is a legit upgrade. I wasn't able to find cans that "perfectly" matched my Ariel cans, but the ones from Krypt were close enough.

My OEM setup with Polk Coaxials:


Putting in the 4 speaker kicker HLCD setup:


With the Kicker 6-pack and painted the grills all black:


You can see in the above pic that the clamps are different.
You can see in this pic that the cans are slightly different. the krypt ones are more 'bullet' shaped. But no one would really notice.