I had not herd of the X600 or X900m but that is interesting. The X900m looks like a X700 with a permanent motor drive 1 attached. I still have 2 X700 and Motor Drive 1 for each. Never had any problems with them but I bought them new and took good care of them. I also wanted a XK but they were too expensive back then. In later years I did get a Maxxum 9000 and still have it. Most of my new cameras are Nikon but still enjoy the old Minoltas. I was working on the Outer Banks today and walked out on the beach and shot a few frames with my X700/Motor Drive 1 and I like that combination.