I've purchased two of these kits, about 6 months apart to go into a i7 gaming rig (i7 930 on a MSI Big Bang-XPower). The memory itself is rock solid, the only issues I had stemmed from the motherboard (Didn't like having all of its slots filled and X.M.P enabled, bios update took care of it). Unfortunately I haven't been able to test its overclocking potential as my CPU (D0 stepping even) is a dud and won't go over 140.
I do however, run multiple VMs on my machine (Arch Linux for development, CentOS to act as a server, Win7 for a sandbox, and OSX for iOS development; usually the two nixes and Windows are running concurrently in either a Windows 7 or Linux host). These obviously suck up the memory, so I'm constantly loading up these modules. Not a single issue once the BIOS update was done. Update your motherboard BIOS if you're having issues! This machine also serves as a 3d gaming rig, and in that respect the memory still (unsurprisingly) works flawlessly.
For the price, this is great memory from a reputable manufacturer. Great speed, great stability, the heat spreader is secured nicely. If you're looking for mid-level/budget memory, this is what I'd buy. Highly recommended.