I can say that most people coming from the razor sharp single chip DLP camp (including me: owned Benq w5000, Infocus 8602, ect) have had no issue with going to different tech and enjoying a very sharp picture. The only thing that I heard that was not so great about the 30es was the lens and it's the same lens as the 50....
However, going by all the reviews it seems that the Sony is sharp and thus far no negative comments on sharpness..........but that could be just RC doing it's thing..........we will need someone to post single pixel patterns with RC OFF to see if the sharpness is really better without RC. If your undecided, just wait for Zombie to get his unit and he'll test it out good and proper!
Also, I can atest to what a great device the darbee is. It seems to be doing something similar to Sony RC, and it makes the image POP. The details just jump off the screen now. I've had the darbee over a week and I'm still impressed with the detail and picture I'm getting out of my Epson 5010. Everyone owes it to themselves to at least try out a darbee.
One thing that I thought about is that the Sony 30 + darbee = 50es