In my opinion, nothing beats a Pronto if you want "unlimited" programming options...nothing. If you have a neo (the original), I don't know why you would look at anything else.
To answer your question, I think the reason for the price being so high is the abilities built into them. The neo is a dinosaur by today's standards (by some accounts, so am I). When you can get the 7000 for about $450.00 and the 7500 for about $650.00, I don't think that's unreasonable. But that's a relative term.