I can only speak for the Nikkor lenses and, as David mentioned, they're great. I have 3 Nikkor lenses and one Zenzanon lens, the 150/3.5, which is excellent, too. The Bronical EC-TL camera body is what I use and I use the system fairly frequently with no problems (knock on wood). If you're adventurous, the amount of lenses one can adapt to the Bronica focal plane shuttered cameras is amazing.
As you've seen, alex66, prices for this system are low for what you're getting so give it a try. Perhaps you've already seen this, but, in case you haven't, here's a website with some Bronica info for you:
http://nikomat.homeip.net/priv/camer...bronica-e.html
Hope that helps.
Marc