Yeah, 460 and 500 is no joke. I'm in an awkward position as we're looking at new vehicles but I'm having a hard time justifying the cost since we really don't "need" a new vehicle at this time and that nothing is really jumping out at us.

6-10k for 500BHP and another 5k for SS headers makes far more sense than say the new X5M or most other vehicles. Obviously the X5M is a remarkable machine but it's also more limited than the 4.8is with regards to towing etc. Honestly, if the X5m had the same tow rating and was available with the optional 3rd row seat, we would already own one. The fact that it isn't, makes it really hard to justify one.

I can only assume one would realize a gain of 25-35whp with headers, mush like the E39 M5. If so, you could very well be around the 540-560BHP mark with the 4.8is with a modest 13-15k investment, assuming you do the work yourself, which is much easier to swallow than the 90-100k the X5M will run ya....