Used car under 7k with fold down rear seats or wagon configuration?

I'm currently used car shopping and I need fold down rear seats to haul my stage piano. To get an idea of why I can't just strap it to the roof or use a passthrough, this this is practically a small coffin. Refer to link for dimensions:

http://www.musiciansfriend.com/accessories/gator-gkpe-88-tsa-88-key-keyboard-case-with-wheels

Here is what I'm hoping to find in the car, and yes I realize these goals are at odds occasionally, so they are prioritized.

Reliable (Honda/Toyota and their luxury equivalents preferred)
Around 2004-2006 model year (flexible)
It can get out of its own way (I find the 3.9L in an 2006 impala to be slow, but I feel like the 3.2Ls in Honda/Acura etc to be snappy enough)
Not going to break the bank on insurance

The only options I'm currently aware of are 2006-2011 model year Chevy Impalas. I was hoping to get a 2004 Acura TL but I just discovered that they don't have fold down seats. Any help would be appreciated.

And no, I'm not getting a truck as I live in a metropolitan area and want to use this primarily for commuting.

Dodge magnum. Far more reliable than any honda or toyota, plenty of room, and 5.7 hemi has plenty of power

Yeah, this is an autotrader question, then maybe autos.msn.com both help you find car hypothetically.