Krell S-550i & Cremona M

Hi,

I'm contemplating to upgrade my 2-channel system as follows:
1) Krell S-550i
2) Sonus faber Cremona M
(Music: jazz, classic rock, female vocal)

Please share your thoughts:
1) Since the Krell can deliver at 550w into 4 ohms, while the Sf has power handling from 50-250w with nominal impedance of 4 ohms, will this pairing cause any damage to the speakers or any issues/concerns that you guys can think of?

2) Is this a good pairing to bring out the best of each component?

3) I already have the JL Audio sub from my existing system. Will the sub add anything substantial to this setup/be a good match to the Sf? Should I sell it to use the funds to upgrade else where in the system?

Thanks,
Mike