Picked up a nice copy from Japan on eBay earlier this week, and I think this going to be a lot of fun to use when the situation arises. I've had fun over the last couple days trying to figure it out and I'm really starting to like it. All shots are straight out of the camera jpgs out of a Pentax K30, going from softest (2.2) to sharpest (5.6), shot on the aperture detents at 2.2, 3.3ish, 4.5ish, and 5.6. I haven't seen much out there as far as good examples of shots from this lens yet so I figured I'd add to the knowledge base!
Bike rack at Chena Hot Springs Resort outside of Fairbanks, AK
Yellow flower, also at the Hot Springs
It definitely is going to take some getting used to, and it's certainly not an everyday lens, but if you're willing to explore it's effects and what it can do there's a lot of potential for some amazing shots with it.