The hard drive in my 27" iMac was preparing to go south so I needed to replace it. And I did not want to pay Apple's extortionist fees to have them do it. It's only a hard drive after all.
Perfect. The suction cups worked great. The step by step guide was invaluable. Took about 30 minutes from open to close and reboot. Honestly the hardest part was getting the lcd and the underside of the glass nice and clean before reassembly.
Take your time and it will be fine. Especially cleaning the lcd and the glass.