original 2007 HD wasn't cutting it anymore. i've had to reformat it several times after booting to a white screen and the computer has slowed to a crawl. i found a 1tb WD caviar black at a great price and decided to try it myself.
great! took about an hour. dust was my enemy, but a can of compressed air and a lint-free cloth saved the day. pressing down on the LCD to remove the bezel was a little scary, but it gave pretty easily.
slow and steady wins the race. corny, but true.