Recently returned to MF buying a 645PRO, with the subject lens plus a 80/2.8N and a 150/3.5C. The 45/2.8 is away being serviced as the focusing action was much stiffer than on the other two, (presumably the helicoid (?) grease had partly solidified through age.
The other day I turned up some very unfavourable user comments which described it as "a poor performer", suffering from "terrible field curvature" and being "very astigmatic in the corners". Although years of experience as a keen amateur photographer have tauthgt me that many lenses can be judged as having such problems when used wide open, performance usually improves dramatically when the lens is stopped down, eg to5.6.or 8. Of course I shall check for myself if this works with this lens when it returns, but in the meantime would apreciate hearing from anyone out there who has (or has used) the original version.
It never gets really good in the corners, but by f8-11 is usable. If you're shooting landscape I'd recommend getting the S or N versions with the 67mm thread or going for a 55 or 35 instead.
The original 45 C does do quite well for reportage/event style shooting though, a good copy will be very sharp in the centre by f5.6 and is usable even wide open.
then I asume I got lucky with my copy because i have no complaints other than weight and stiff focusing + 77mm filters..