Nice to meet you back here from time to time (1st time 10 years ago!)
So, yours is the older 55/1.2.
I've got the newer (and relatively more expensive) 50/1.2 and used it quite a bit with my D200 (mainly on stage):
Yes, this is @ f/1.2, too.
What I think you will appreciate when using it on an FX body (I've got the D700, recently) is the much easier manual focus through the optical viewfinder - really no need to use the LCD viewer.