The difference is temperature, especially only being 10 degrees is insignificant. The speed, however, does seam to be very different. There are many factors that could cause this?
More factors that could cause differences in speed, is how full the drives are. Also if your system is accessing the drive when doing a test that could be affected. Also the speed test that you run, depending on the setup can yield different results.
I would do random tests over the next couple days to see if you get different results.
Let me know.
Jared PicuneCalDigit. Serious Storage.Denver Final Cut Pro UGGeeky Mac | FCP Tips & Tricks