If you're not the type to use GPS very often, and have a data plan with plenty of space, then something like TeleNav does have its appeal.

PLUS

• Convenience of all-in-one device
• Good POI search options
• Ideal for pedestrians

MINUS

• Monthly subscription fee; eats into data plan
• Awkward route recalculations
• Spoken directions are sometimes delayed

Rogers Wireless has an exclusive arrangement with TeleNav, an American company that creates maps and mapping software for BlackBerrys and smartphones. I had to download the 1.5MB file onto the Samsung Jack, where it installed automatically.
Rogers changes $10 per month to use the service, on top of whatever data plan you already have. In addition to the $10 subscription charges, you'll have to pay for data usage, because searching for POIs and using the mapping software will eat into your data plan. If driving to a destination takes you an hour, and you have TeleNav running on a smartphone the whole time, you'll be using of data. I asked Rogers Wireless how much you'd use up during an hour-long jouney, but they couldn't say.

U.S. maps are available as well; but if you use TeleNav for navigation when you're travelling in the U.S., you'll face roaming charges along with your data usage.

Currently, TeleNav doesn't offer traffic reports. When that feature arrives, it's a good bet that it too will eat into your data plan, and there will likely be an additional subscription charge as well (as there is for traffic reports on the Garmin system).

TeleNav was better at separating POIs into different categories than the other two units, providing more extensive options. For example, I could look for an Asian restaurant and narrow it down between Chinese and Vietnamese. And because the Jack has a Web browser, I could take my research further than I could with the other two devices. But again, that consumes data.