I assume the sat nav units are pretty good in the omega's then?
Absolutely featureless. All it can do is get you from where you are now to where you want to go. The biggest gripes from most people on here are the gimmicks like no postcodes and no speed cameras.
*BUT* despite being a 15yr old system, it is still a million times better that the most modern, poxy portable units that every idiot sticks in their line of sight. It has the advantage of speed signals from the axles and gyros to allow it to remain reasonably accurate when the portable units are in pure guess mode. (The older CARiN unit, you could actually get away with using for a few days with the GPS aerial unplugged!)
My last TomTom unit is somewhere at the end of the Aston Expressway, as I expect a single function device to do exactly what it is supposed to do. It didn't, so I ensured it never pissed me off again. I never bothered to replace it. I'd rather have an old proper, built in one than a poxy portable new one.