I've had PC desktops and laptops for years, like since the mid 80's including building, writing software, using all sorts of applications, modifying, upgrading and fixing them. Overall I've not had big problems with any if my machines, but last summer when my graphics card failed, I felt like it was time for a change and bought an iMac 27.
So far I have to say I really like it, very elegant design, excellent screen, boots quickly and has not crashed..yet!
But it's not without its frustrations, like not being able to simply transfer files from iPad (iOS) to the iMac (OSX). I think this should just work, but it doesn't. I don't understand why Apple's own Airdrop facility is incompatible between iOS and OSX... A real WTF moment to me.
Another issue I came across was Outlook pst file incompatibility between windows and OSX versions. That needed a bit of a work around, which was a bit of a pain.
However on balance and FWIW I'm enjoying the iMac and may in the future get a MacBook, though the iPad with a Logitech Bluetooth keyboard is very useful and perhaps almost a MacBook Air... ish..