Go to esupport.sony.com/US/perl/index.pl
and download the owners' manuals and manufacturer's code list for each remote and compare them for your specific needs. I am sure you'll go with the RM-VLZ620 since it was just released and covers every component you can imagine. I just bought one and it works with all my AV equipment, as old as 14 years and as young as one month. I also notice the codes are 4 digit for the 610 and 5 digit for the 620.