I've had this machine for around a month now and I must say I'm very happy with this system.
I bought the machine with 16GB ram and have been running a HEAVILY modded skyrim on ultra graphics for the better part of 2 weeks on it. The graphics are just jaw-dropping and the PC chews it up like it's nothing, the game runs perfectly smoothly no matter how much is going on on-screen. The SSD makes a huge difference too I think, windows boots in under 10 seconds and loading times in skyrim are very fast (I barely have time to read the 2 sentences of text displayed on the loading screens).
I'm not sure whether I'm meant to mention the service, given that its a PC review, but just wanted to say the service was excellent. I received great advice in my initial phone call and was updated frequently via email throughout the build/testing process. I received my machine within 2 weeks.