Questions on KT150 tubes

I have a Jolida Fusion 3502 with KT-150's. I think the same model that Wolf and a few others here have. I have to say for under $2K retail this integrated amp sound amazing. I am using a preamp with it and using just the amp part but holy cow! Superb late night listening, big, wide and 3D sound stage. It has clarity, a touch of sweetness and detail. I smile every time I listen. I started with the EL-34 in it and still love them, but the KT-150 are stunning.

Could any of you KT150 aficionados comment on the break in period for these tubes?  I bought a quad to replace the KT88's (Gold Lion reissues) in my DeHavilland 50A mono blocks (after the OK from Kara Chafee) and have maybe 60 hours on them.  They sound tonally more bleached out and not any more dynamic than the KT88s.  Have I not given them adequate break in time, or does this particular amp possibly just perform better with the KT88s, with which it was voiced??

If you are not crazy about what you are hearing after 100 hours, maybe they are not for you.

Is the bias adjustable? Can you lower it or raise it a little to change what you hear? Lower bias will warm up or sweeten the sound, to a certain point.

what is/are the price(s) on the KT 150 ?

$95-105 each depending on matching and quantity.