Listen bud, your a idiot. Ill explain why.
The SPK Kaos is a wide boot, slightly wider than the foils. They are also relatively soft if you are over 130 lbs.
The Kryptons are very narrow, MUCH narrower than the SPK's. They are also a pretty stiff boot, more all montain orientated.
There is no way in hell that both of these boots fit your foot. Everyones fott is differnt, and requires a different boot.
I would paste the link to my boot fitting thread here, but I hightly doubt you will even read it.