Hasselblads are excellent system cameras. You were just unlucky and picked a bad one and that can happen with any type of camera.Ever since falling in love with 6x6 film while in photography school using a Mamiya C220, my first 120/220 camera, I've been had an interest in classic Hasselblads.
After finally setting aside an even $1k to invest in a 500CM system (body, A12 back, WL finder, 80mm CF T* lens) I've been rather underwhelmed with the overall experience.
Starting off, I chose to purchase my kit from a local mechanical camera repairer/reseller whom I trusted: Ken Toda at Humaxx Co. in Archdale, NC (over eBay, KEH, etc). But the only Hasselblad body he had in stock was a well worn 500CM. So, from the get-go the idea and prestige of the perfect Swedish/German machine was a bit tarnished.
Jump forward to having used it for well over a year and finally getting past the 500CM's film-loading learning curve (compared to the simplicity of my old C220) and loving the size and versatility of the camera, I'm left with two problems I've yet to fully solve: light leaks and poor focusing.
The light leak problem is not film slide related, but due to wear to the Magazine support hooks, possibly wear to magazine catch hooks, but mainly wear to the thin interlocking ridges on the back plate of the 500CM's body. That problem can be (temporarily) solved with about 10˘ worth of gaffers tape covering the gap between the back and body, but is annoying. At this point I'm resigned to this being practically unfixable..
I've thrown more money at the focusing problem. Investing in a much brighter and contrasty Maxwell Precision Optics Hi-Lux Brilliant Matte focusing screen as well as having the body overhauled by Bill Moretz at Pro Camera Inc in Charlottesville, VA (at the recommendation of Bill Maxwell) I've already set myself back a few hundred bucks, just shy the price of a new 500CM body. But my soft subject focus / out-of-focus problems still persist.
I've switched back to my Mamiya C220 for the past few months to see if maybe my eyesight/focusing ability has become poor, but my photos are still coming out sharp on my C220.
As much as I like the idea of having my equipment properly maintained and repaired over tossing the damaged and buying new.. I don't know if that was so smart this time around.
I'm curious to know how other medium format shooters may have been disappointed in their 500C/M's, especially dealing with focusing, light leak, or age-related problems.