Little bit of history... I originally purchased SR 15" MBP back in Jan 08 of 2008. After few months of use, I started to notice the following issues: 1. MBP not waking up from sleep. 2. If it does wake up, mouse movement is sporadic. 3. If it does wake up, WiFi connection would be lost so I would have to disable WiFi and re-enable WiFi in order for it to connect to my network. 4. WiFi wont connect to my network even with the correct password. 5. Trackpad movement is very "jerky". Being fed up with these issues, I spoke to someone at Apple and they replaced my laptop. After getting my replacement MBP with a 15" MBP Penryn model, I no longer have these issues. I even have iStat running. I know that a lot of people are having these issues so perhaps its not the software that's causing these issues but actual hardware.