Not sure where your GC stutter is coming from.
I am using 48 Samsung 830 128GB without any OP in my workstation and I would rate the load as I/O heavy. With complete writes (meaning a full disk), immediately deleting most of the files, rewriting again and again without any pause in between. I've had a few days where the avg. I/O rate stayed above 10 GByte/sec uninterrupted for the whole day - producing close to a petabyte transfers.
Have yet to see GC stutter with the samsung drives.
wrt to cooling:
I am using Sharkoon's 6bay enclosures in my workstations. They were the most dense I could find (and reasonable priced)
http://www.sharkoon.com/?q=en/node/1824
rgds,
Andy