I've only changed cases 4 times
1. When I went from the horrible Packard Bell case to a smaller Antec back in 1997
2. When my brother gave me a new case with 120mm blowholes cut into it in 2001
3. When I decided to buy a used Antec 3700AMB because it would be smaller, lighter, and would cool better with some mods, plus it was recommended by SPCR for being a cooler case
4. When switching to an Antec P180 - I got it solely for the thicker panels to help keep in sound and the indirect air intakes in the front that had a higher quality plastic than the front of the 3700AMB, giving less of an "echo" noise when the air gets pulled in. Frankly, my 3700AMB cooled great and despite the constant touting of the P180 being an awesome case for cooling, I saw no improvement. Like the pads isolating the panels and PSU from the case though; should have included some isolators like with the Sonata II. Then again, other than the isolators, all of Antecs new designs make the Sonata series, touted as being quiet/silent look like crap anyway.