I think having a chance to see and try the models is most important.Plan a day when you can sit down and find out how "user friendly" each one is. You will certainly be reading through the manual to understand the operations and all the options, but some synths are much easier and almost common sense than others. Find a dealer who will allow you to use the synth along with the manual so you can check out how easy or complicated it is to play,program, etc. Shopping out the price is the easy part.