I just picked up a Beseler "Color-Pro" 50/2.8 enlarging lens with some other equipment last week. It is a very nice looking lens, and appears to be a 6-element variety - but I didn't expect too much from it. I finally tried it last night and all I can say is "WOW" - it is a fantastic lens - I made a 11x14 enlargement at 2.8 just to see how it would do - sharp corner to corner and great definition. It appears to be easily comparable to my El-Nikkor and Componon-S lenses. Best of all, I got it as a freebie with the other stuff I bought for $20 total.
Just a heads up that this is a good sleeper lens that can probably be found for cheap prices.