It depends on where you place your monitors... Cardiods are best at rejecting monitor feedback when the monitor is directly in front of the microphone, supercardiods are better at rejecting feedback when monitors are more to the side (as most keyboard players have them)...

The frequency plots show a slightly more aggressive upper mid peak in the 105, but I'd be prepared to say both would probably blow away anything you've heard to this point in a handheld.

I think matching the type to the monitor placement is probably the most important consideration...