Skip going out to dinner a few times and spend a little more. Your ears will thank you If you get the Kappas, they really really need to be amped to make the most out of their capabilities.
I chose not to do the +3db on the tweeter, but should I?
I would definitely say do it. If you look at the angle of where the tweeter is aimed and how the speaker sits in the door, you'll notice that the tweeter points down and away. When you turn it to +3dB it aims the tweeter up and back, more towards where you sit. It helped even better when I kicked up the treble through the deck. I've gotten a lot of compliments from how it sounds despite the lack of an amp.