Mark III Cabinet / Speaker ? Vintage 30's??

I have a several different cabs I run with my Mark III's.
An old 1960A cab with Greenbacks.
An Avatar 2x12 & a Marshall 8412 4x12 detuned with 2x12's in it (which is my favorite).

I have 4 V30's, 4 greenbacks & 2 V128's.
I thought my ears were messing with me so I swapped out the speakers & interchanged the cabs and
the Vintage 30's sound less harsh than the other speakers. Even the rolled off top end V128's..
Did multiple recordings & stayed with the Avatar & 8412 for most of the testing..

I still think I'm losing my mind..
Is it the way V30's match up with Mark III's??

If it works, it works. My Mark III has been out of commission for a little while but I used to play it through a Rectifier vertical 2x12 with one of the speakers replaced with an Eminence Tonkerlite. It always sounded great. What I'm really looking forward to, though, is getting the amp back from Mesa so I can try it through the metal grill vertical 2x12 I just got with the EVM12Ls in it.

I run my Mark III (blue) through a Carvin 4x12 with V30s and it sounds great to me. I keep the presence very low (1-2 range) and there is no harshness at all.

I think for a sealed cab, the V30 is the way to go. I didn't like it in my open back combo though (too nasally) so I put a 75W Creamback in there, and it sounds **** good.