@hiroh Congratulations! You're about to discover something wonderful. As others have said, Hasselblads have their quirks like any other camera. For example, the sounds they make can be polarizing. To me they sound AMAZING. This is what makes them so engaging and satisfying to use.
Now... to your question:
First of all, here's a
useful web page with all the models. Allow me to be direct and prescriptive here, but I strongly believe that the best 500-series body is the
501CM. Here's why:
- They are the newest, manufactured up to 2005. It's easier to find a truly mint specimen.
- They come with a better stock focusing screen called AcuteMate D. The part numbers of these screens start with 422xxx (instead of 421xxx the older series used) and they alone go for $400+
- They have the gliding mirror feature which reduces vignetting on longer lenses.
- They are coated with the Palpas material inside, which is prone to crack (which is harmless) but supposedly decreases internal light reflections
- They are much cheaper than the higher end 503CW model, which adds TTL flash metering and a motor winder.
I would avoid the 503cw because strangely they command a noticeable premium over 501cm, but their TTL metering is nearly useless. The required SCA modules are hard to find, and there's only one (quite quirky) native TTL flash in existence that works with the system. After almost two years of searching i have not found a single Hasselbad ProFlash model on eBay with the native TTL Y-cable. Basically, Hasselblad TTL flash metering is a dead feature IMO. The only benefit of getting the 503cw is the ability to attach a motor winder.
The older models work and feel largely the same. They are cheaper, but they lack the bullet points above. If you decide to go with a 500C/M, my advice would be to upgrade the focusing screen and to make sure you get the latest-style WLF. But once you do, you'll find that you're spending 501CM money anyway.
Also, and this is something that nobody mentions for some reason, stock WLF magnifiers on 500-series have a diopter adjustment of 0. This means you need to have a perfect vision or wear glasses to focus comfortably. I had to buy two additional magnifiers: -1 for now, and -2 just in case my vision gets worse over time. I do not like wearing glasses when I'm taking photos.
And finally, let me also suggest the 60mm lens as the starter lens instead of a more common 80mm. First, you already have the Rolleiflex if you want this focal length. Second, I found that the 60mm lens trivially does what the 80mm can do, you just need to zoom on your feet a little bit. But every once in a while it can give you a shot the 80mm cannot, when you are space-constrained.