A Mamiya 645 Super was my gateway into MF after almost ten years of 35mm only shooting. Ergonomically, it's not the greatest without a winder grip. Until I got one, I probably wasted at least 2-4 shots per roll fumbling with its odd boxiness and hitting the shutter button in the process when studio shooting with strobes. The grip makes a huge difference. The extra weight isn't that big a deal relative to the convenience. Drives are a bit noisy. That's their main drawback.