"Excellent case for low-noise & low-to-medium heat uses."5.0 starson by SunnyDanSan
Pros: Quiet. Great drive mounting. Softer lights (compared to prior generations of Sonata). Adequate PSU for most applications. Excellent heat dispersal for low-to-medium demanding tasks.
Cons: The 17-ish-inch tall case feels a bit tight when wiring, compared to some of the 20-inch tall options (when using a full ATX board). Not the best case for multi-GPU high-load, high-heat situations.
Summary: I am an avid fan of Antec cases and power supplies. 3 of 4 of my post-Amiga computers have been Antec cases. I own a classic Sonata for my now 9-year-old (still on original PSU) single-core XP gaming machine, but that's not what I'm here to review.
My Brother In Law asked me to spec him a new machine just over a year ago. Quiet was his number one concern. I, of course, looked at the Sonata line. The Sonata III has several improvements. First, it has rid itself of the ultra-bright LED lit domes so it doesn't light up a room anymore (gaffer's tape still recommended for the two small lights, if in bedroom or dark-tv-viewing area). Next, it has a bit more space around the PSU than the original Sonata, so swapping power supplies no longer requires unmounting the MoBo or processor fan. Last, they've upped the stock PSU to 500 watts, which is enough for most non-SLI and non-CrossFire applications. They do offer the Sonata Proto, cheaper, and without a PSU, for people who want to build with a more powerful PSU.
Of course, to build a very quiet machine one must be mindful of the noise made by other components (HDD, DVD, CPU cooler, Video Card Fan) and buy appropriately. My Bro-n-law's machine is so quiet that one must put their ear to the case to hear it run; but note that we used a fanless video card, quiet drives, and replaced the stock CPU cooler with an 24dBA max fan/heatpipe.
Besides the above notes, the Sonata III uses the classic dampening tricks: Silicone grommets on drive mounting; quiet case fan... etc.
My next gaming machine will be a Sonata Proto or Sonata III case; but note that I never use multiple video cards and never overclock, so I am not too demanding for heat dispersal. I would not recommend this case for SLI/CrossFire setups.