I have Mark Stonich's (bikesmith) 155's on one of my bents and knee pain in theleft knee went promptly away. Love em!
I just bought a Rans V3ti and the only thing I'm not sold on is the long cranks. They are carbon fiber cranks so they can't be shortened. If I start getting any knee pain I'll have to look into switching. I'm hoping this bike will be so light and nimble that my knees can take the 175's supplied with it.
If not, I'll have to call Mark back. He's sure a great guy to talk with! He has lots of advice.
I think one of the reasons long cranks work OK on uprights is that on an upright your body is continually more or less bouncing up and down and compensating for the length, in fact, taking advantage of it with the weight of your body. But you can't do that on a bent! So knees tend to pay the price.