Josh sorry it took so long to get back to you and congrats to you.
I'm using morel hybred interga 4's they also come in 51/4 and 61/2.
From what I remember at high volume it starts to fall apart, your seat localized from the port. Also the top end (high feq) strays. I think a 51/4 point source would work better. And yes I do like what your using now but off the window I think a point source holds up better. Something about the tweater in middle of the mid and everything hitting in one spot. I would get in your car with a meter if you can hit 120db with no seat problems I would toon for sq their if not make a cork for box and see what happens. If you have any questions call me 714-448-8852 if I don't answer leave a message and I'll get back to you.