KEY POINTS:
The Blackberry is telling me: "Turn left." The Navman says: "Turn right."
I consult my road atlas and drive straight ahead.
I've been tasked with assessing the relative merits of a Vodafone Compass-empowered Blackberry Pearl 8110 against a Navman S50, and this unfortunate experience comes toward the end
of my three-day trip.
If this were an out-and-out beauty contest, the Blackberry would win hands down. Earlier Blackberrys looked like squat home label printers, but this latest generation is the same size as a mobile phone that manages to fit a mini-qwerty keyboard on to its sleek face.
The Navman, on the other hand, looks like it was styled by an East German in the 1970s - hard edges, impenetrable and big - until you turn it on and the LCD screen comes alive with a well-designed touch-screen system.
The Navman's operation is intuitive and easy to read. When searching for a destination, you type in the location and set the thing going. In no time at all the Navman displays a map in 3-D or 2-D, or guides you by each turn from your current location.
A rather friendly, almost recognisably Kiwi voice soothes your passage with recommendations to turn left or right and the distance until your next turn. If you choose to ignore her advice, she delivers a reassuring "recalculating" whilst she works out an alternative route.
Apparently, more advanced Navman models have a built-in camera and hands-free calling kit (but you need a mobile phone to plug in to), whereas the Blackberry has all these things, and more, as standard.
Yes, the Blackberry is many things: mobile phone, web browser, still camera, video camera, personal organiser, calendar, note taker, email organiser and GPS navigational system.
Whereas the Navman is relatively simple to operate, the Blackberry requires some instruction. Once you learn how to programme a route, the map isn't automatically displayed and several more stages are required to bring it up.
Again, there is a choice between a map or turn-by-turn guide and a voice that assists you: this one a generic, male computer voice with an American twang that makes you think Stephen Hawking is over your shoulder.
And, when I disobey the instructions, it says "re-routing" to rhyme with "outing", instantly pricking my Anglo sensibilities.
But, if you turn the sound down, the small screen makes it very difficult to see the map and drive at the same time.
Despite this failing, I really like the Blackberry because of its multifunctionality, the fact that I can carry it around and because it makes me more attractive.
The Navman is a great navigational aid and will look fine in your parents' car, but I'm taking the Blackberry. And turning left.