We have had upwards of five different VTech systems too. They have always worked well for us. But no custom ringtones per se.
With cellular taking over most home phones of late, it's probably a moot point, eh?
VTech seems to have found a way to pack-in a lot of popular Cordless Features at a cheap(er) price..but as of yet..I haven't found ONE with Custom- Assigned Ringtones capability.
OK, what am I missing?