I have the 7.25 in the front on mine and the boom 5.25 in the rear. I have to tell you that the 7.25 are not that much better than the 5.25. Plus I would be willing to bet that they are made by the same manufacturer.
Don't get me wrong the 7.25's sound really good but at speed it really is not that big a dfference. I am driving both with a 400 watt 4 channel amp so loud is not a problem, I just wish they had more bass.