The Surface Pro 2 vs Laptop Dilemma

Hey Tribe!

I'm trying to figure out what my next computer purchase is going to be, and I figured it would be a good idea to get some input from you guys.

A little background on myself. I am a mechanical engineering student about to graduate this December. Current'y I have a five year old Dell Inspiron that has served me well through college and my wife's Surface RT that I have more or less claimed as my own. I typically only use the Inspiron to casually play League of Legends on ultra low settings and run Office, and I use the school's desktops for modeling software. I use the Surface RT for just about everything else. (I probably would use the Surface for Office if I had a type cover but all we have is the touch.)

I have a job lined up starting January and will finally be in the market for a new computer! I want a compact, touch screen, premium device that can run League of Legends, some light Solidworks, and some simple recording software. I'm currently stuck between the Surface Pro 2, 256gb, 8gb w/ type cover 2, docking station, and new monitor or a new Dell XPS 15 fully-loaded. The XPS is an extremely powerful machine and would definitely be a huge jump from my current laptop, but I love the idea of having one device that works as my tablet, laptop, and desktop. I'm pretty sure either device would fulfill my needs just fine. I'm looking for insight on which set up you prefer. Price is not an issue. First hand experience with either device would be great!

Get the XPS and keep using my RT as a companion device or get the Surface Pro 2 as my all-in-one computing device?