I just went outside and tried mine and the rears still shook the neighborhood. Of course together they kick a$$ but it was still plenty loud with just the rears..

 

I must have one. How much is that thing?

 

It's an older model so you can probably find it for around $600 now.

I'd personally get the Pioneer AVIC-F700BT or the new AVIC-F900BT. They both have the maps stored on flash memory so there's no need to pop in a nav disc. The F900BT also supports MSN real time traffic service (free for first 3 months, $130 for lifetime), which delivers traffic updates, local gas prices, etc...

It's what I'll be putting in my HHR come August .