i built in the 240GB Extreme, updated to R201 and have Benchmark Results of about 200MB/sec write and 260MB/sec read on a MacBook Pro 13" Mid 2010 (Blackmagic Disk Speed Test). Connection Speed is 3GB. A 230MB videofile can be duplicated in 1,4 seconds.
After a night in Suspend Mode it shows only 100MB read and 130MB write. Duplicate the files needs 4 Seconds. After a reboot the speed is back to 200/260. If i switch to suspend and back on it has also full speed. But on the next day it is always slow.