If you have no plans to change IP's in the forseeable future, is there any disadvantage or reason not to set ttl's to one week for example instead of cpanel's default 4 hours? Would this not increase speed for those browsing and also reduce unnecessary dns load? Why not set longer ttl's?

Indeed why not? cPanel sets them far to short. One or 2 weeks is fine if you don't forsee any zone changes.

Thanks Kevin!

Just wanted to make sure I wasn't missing something obvious For my own sites especially that haven't changed their IP's or anything about their zones in a year, makes sense to put them at 2 weeks then. I'm now on a new satellite connection here with 600-700 ms latency, and found myself wondering today why I'm waiting for dns lookups for my own sites... and then the thought occurred to me : well even if it's only an additional 5 ms for a broadband user, why make them wait (even if just a tiny tiny bit) for absolutely nothing? Thanks again for setting my mind at ease so I can proceed with the obvious...