WHICH ARC LINESTAGE TO REPLACE LS-15?

Hi,

I'm looking to upgrade my LS-15 to one of the following linestages:

LS-5 Mk III, LS-16 Mk I, LS-25 Mk I, Reference One, Reference Two Mk I

How do you compare those against each other? Please share your experience if you owned any of them...

I like the sound of 6922 tubes... How does it compare to the sound of 6H30 in the more recent LS-16 Mk II, LS-25 Mk II, Reference Two Mk II?

My system as follows:

Wadia 830
ARC LS-15
ARC VT-130SE
Sonus Faber Cremona
MIT Shotgun S3 IC & SC

I listen mostly to Classical Baroque and Jazz instrumental & vocals

Thanks for your advices!