The laptop is a pretty sweet setup, and would run the games you're looking to play, so it's really down to a personal preference of yours on whether you want a computer that you can take with you or if you want a computer that you can build yourself and probably get a better setup with the same amount of money. Sorry for the run on sentence.
As for the desktop:
Your RAM is rated at 1600MHZ while your MoBo supports up to 1333MHZ RAM. Don't worry though, it will still work as RAM is backwards compatible. I, however, would suggest getting a MoBo that takes advantage of the RAM's speed. Here's
one for just a little more than you're paying for the current MoBo.
Personally, I would go with the laptop, just because it's mobile and I already have a desktop.
Anyone feel free to chime in here, but the current build you have, I would think that the laptop is a little more powerful, but then again, I haven't seen the benchmarks or comparisons on the GPU (Vid Card) you listed so I'm sure there will be some discussion about that.
There's my feedback
Edit: Welcome to CF by the way!
Humans are the only creatures that won't live up to the their potential. Give everything your all. When you die, die on E.
So I ask you, what do you intend to do now?