1. Quick input
2. Smart routing
I don't mind technical, complex devices. But a GPS input should take no longer than a pause at a red light. And for this, the TomTom does it's job. Roughly takes 10 seconds to input an address. I completely agree with you stromdriver, going to a long list of POI is painful (and not TomTom like). But you can switch to a search mode which is a 'little' better.
For routing, I throw challenges at the GPS. It's easy to show stupid GPS over clever ones.
Sydney is a complex city with hopeless design (thank you to the British). GPS systems HATE Sydney. And no GPS system knows the back streets of my old neighbourhoods and it's shortcuts like me.
Throwing all the GPS systems through the rat traps, knicknacks, and backtracks of my neighbours hood none know the good routes.
The routing is extremely clever, although that said..... It's proven in Europe (where tricky routing is required). And TomTom is married with maps from the various countries (TomTom has no control over the maps in most cases).
So I know it works great in Australia. I cannot speak for Canada and the US.
Now to the voice recognition....
All the current TomTom products have been prepared voicewise for the Australian market. The Voice recognition is pretty well trained.
This is NOT the case with the Mazda NB1.
They've rushed the product to the market and have not yet had a chance to include the proper Australian voices (i.e. computer voices).
As a result, we have to use the British voices and recognition, which have far less ability to recognise Australian pronunciation.
So far .... 3/10 for Voice.