I have had some dealings with Mike Fourman and can say that I found him an honest and reliable dealer. He can be a little difficult to contact sometimes because he travels a lot on business.
With regard to the Kiev camera I own a Hartblei upgraded model which is compatible with Hasselblad backs. I have further upgraded it with a Hasselblad Acute Matte focussing screen. One of the nice things about these cameras is that because of the Pentacon Six mount they will accept a wide range of Zeiss Jena and Schneider lenses. These are very good lenses. The number of sources for buying modified Kiev cameras is increasing. Not only do you have Kiev Camera but also a company called Arax (website www.arax.com) They provide a similar service to Hartblei but refuse to make the cameras compatible with Hasselblad backs. It is their opinion that the engineering required to do this stresses the transport mechanism to an unacceptable extent, although I have had no problems.
For research purposes you should visit the Kievaholic website as previously mentioned plus www.delphiforums.com and search for a forum called the Kiev Report. Also www.photo.net there is a special Kiev section in the Medium Format Digest.
Feel free to drop me a private message if you have any other questions.