7. Why ATI or NVIDIA, why Intel or AMD?
I think Intel for CPU, but just for my rigs. I build many rigs for friends every year, and depending what they want the rig for and the money they want to spend I choose the best performance/price available at that moment. That means that sometimes I recommend Nvidia and other times AMD. For mediacenters with little gaming capabilities, I usually recommend AMD's APUs.
This time it seems that the "bang for buck" of that first shipments of R9 290 unlockables to 290X was unbeatable, after all I was going to put the card on water. Heat using air cooling was the only problem I saw on this first non-custom cards.
8. Does your PC live up to your expectations ?
I'm pretty sure I could use this rig decently for more than 4 years, but it's not about for how long I can use a rig, it's about building the rig.