To quote Ctein:
"The single most important piece of photographic
equipment you’ll ever own is your enlarging lens."
I am once again setting up a darkroom and will start with EL-Nikkors based upon my experience with a 105-N that I used before. It was a very nice lens. It is my understanding that with all EL-Nikkors the later plastic appointed ones are better than the prettier all metal ones. With the 50mm, the 2.8 is significantly better than the 4 (six vs. four element).
When circumstances permit, I will probably acquire some of the latest greatest German glass (Apo-Componon HM, Apo-Rodagon N) but I will expect the improvements to be subtle.