My Favs won't work on the BlackJack.
The Dash and the BlackJack are both nice phones. There are a couple key differences between them. The BlackJack is 3G which means supper fast download rates (if you're carrier is also 3G). The Dash supports WiFi which means.... well, WiFi access.
I prefer the keyboard and layout of the BlackJack. I don't care for the keyboard on the dash. However the dash does have a much better battery life.