I have the Proton 8. The Krypton is a more expensive / higher end boot.
I don't know how much the Krypton's weigh, but in my opinion the Proton 8 is pretty heavy (for freestyle especially).
I've played with the Krypton Lotus or something like that, its a purple freestyle boot from Dalbello's 07-08 season I think.
That boot was like night and day difference in weight.