Hi Glen. I hope all is well. You may recall that we have previously privately discussed home wiring and grounding. I am glad to see that you are still enjoying LD's. You are not the only one. I have owned several of the below, and can offer the following thoughts. Ranked in descending order, I would offer the following as good choices.
CLD-79: personally watching for one of these at a bargain
CLD-D704: my personal favorite and a terrific piece. I personally have not seen anything better in LD.
CLD-D606: reference piece of M. Fremer for many years. I just bought one on ebay very inexpensively.
The CLD-59 is of the same vintage as the CLD-79, and represent late model Pioneer production. I do not have experience with it. The main weakness of the CLD-D606 is that it only has Toslink digital output, as compared to the CLD-D704 which has both.
In terms of souring info, if you are not aware of it, the following may be a useful source:
http://www.fivechannels.com/hardware/laserdisc_archive/pioneer/pioneer_ld_archive_date.htm
Gary