Lets see.....
I have had one bad Apple product since 2000 and they are piled up all over my house.
I have 2 iPod touches still going strong after 2 years
I have 5 iPods still all working after many years the oldest is the Silver Model first issued iPod Mini.
I have 2 Macbook Pros and a Mac Mini all still kicking after many years of use
I have a Airport Extreame and 2 Expresses for the last 5 years working on a network that has gone down twice in 5 years, simple reboot fixed it.
Now on the PC side, I have a very old P4 Sony Viao still kicking all my Dell gear is junk! Which includes my current Vostro POS! I also have a Studio One that I bought for my kids that I have to reboot once a week just go get it to work. So I say if you had bad luck switch back, as I have to Apple products because they usually tend to last long for me and hold there resale value better.
Now as far as the iMacs go, I personally think there was an issue with software that created hardware failures and Apple is not going about it in the right way, so I wouldn't doubt we see some type of class action lawsuit of some kind, this always seem to happen with just about any electronics company.
My recommendation is buy a decent case for iPads/iPods, my kids have dropped my first generation iPad several times, no worries as it is in a Otter Box case thing still looks brand new. 😉 A $1700 machine should last you much longer than 4 years, I am going to buy the new iMac and if it doesn't preforme like it should I will be looking at Windows 8 Machines as well. The new iMac should include the touch screen, and I am suprised they are not, **** I could get another Mac Mini and a new touch screen Sony for the same cost as a new loaded iMac. LOL So I do feel your pain, but for me the devices for Apple have been rock soild with the exception of my 2011 iMac i7, Lion messed it up in my book, just glad they gave me instore credit.