So I got this lens recently in R-mount. Originally had the previous version on order, and my dealer ended up getting me this instead - great guy BTW.
I cannot compare lens performance to the non-ASPH version, but this lens is super sharp, and super tiny. The Big Booty extension box is not the most ergonomic, but no choice there.
Today, I just got a bonus when I found out the IC on this thing is 150mm The previous version I believe is 110mm.
Just looking at how much is usable, but this is just fantastic!
Here's the excerpt from SK site:
"This is a completely redesigned 120mm f/5.6 Digitar lens in a Copal #0 Shutter. It will stand up to the performance demands of today's high resolution digital backs, allowing you to bring the swings and tilts of traditional large format photography into the digital arena. The implementation of Aspherical Lens technology makes this lens extremely versatile with an incredible 150mm image circle"