just for sharing,i'd just bought a KVR kingston from a shop in lowyat.they gives warranty to 1 on 1 change to other ram if it's not stable.just did the memtest last night,everything's working fine and seems like no problem until now lah..
btw,the removing battery ribbon only apply to latest macbook pro(the one comes wif internal batt)if older one,i think u just have to remove the battery and it's safe edi.