Last spring I bought my first medium format camera through KEH. I didn't like bidding on e-bay. If you "win", it really means you are paying more than anyone else. I had decided on a Mamiya 7, and they were selling for about $200.00 more on e-bay than at KEH, and KEH has a good return policy. My system, even used, is pretty expensive, but I felt it would be the best for the way I shoot. Just do your homework.
Having said that, I've been shooting all summer with this camera, and just started printing in the last few weeks. I had been shooting with a Nikon F100, which is such a souped up camera, and very fast to shoot with. The Mamiya slowed me down big time! Loading the film, focussing, advancing the film manually (something I keep forgetting to do! It was so natural when I first started shooting way back when in high school!) Although, I don't like to "edit" while I'm shooting, I do find that I am a more deliberate shooter, and I always have several extra rolls of film in my pocket. I do find that I have to sit down to change the roll, and with only ten frames per roll, I start to really observe what I'm shooting more carefully. My husband thinks it takes me too long, especially when we are out for a walk, but he'll learn to deal with it! Besides, with practice, I should be able to work a little faster. My subjects are frequently my kids, so being quick with the shutter release can be key! So far, I'm very happy with the results.
Keep in mind that having medium format film commercially processed can add up, so if you can stick with b/w, and develop it yourself you'll be saving untold millions of New Zealand "pesos".
You will be amazed at your photographs, and your shooting will get better, and the end results will be gorgeous! Good luck