I just received my AO Spencer Series 4 microscope. It's in good shape, and I got it because I don't see Series 4 models around much. Now that I have it though, I question the wisdom of my choice because I need to clean and adjust a few things but I can't find a manual for it anywhere.
There's a great microscope support group over at Microbe Hunter, so if you're into microscopy of any sort, you should take a look and consider joining their forum.