First post here, so please forgive any newbie mistakes. I'm finally making the switch from PC to an iMac (most likely). I was looking at the 2.8 24-inch as the best option for me. If I can find one as a refurbished model, (1) what experiences have you had with refurbished Apple/Mac products? (2) Which retailers, other than the Apple Store refurb, have you used? Thanks for all input.