As mentioned already, pretty much any modern computing device available will cater for your needs - functionally.
However, one of the things that drew me back to a MBP (I had a MBP in 2007 but ditched it after a year and switched back to Windows 7) was the "feel".
In my university days in the late 90s, one of my professors said that with the power of machines always increasing, the most important thing about a machine will become the bits that you physically interact with - i.e. the screen, mouse, keyboard and to a lesser degree the case - and these are the areas where you should spend your cash.
With a rMBP, those bits are very well catered for in one machine. The retina screen is very high quality, the mouse and associated driver is one of the best currently available I believe. I have tried various other trackpads/gesture surfaces but they just dont feel as good as the glass trackpads on the MBPs - and by feel I mean the way the cursor behaves in realtion to your inputs so not just the actual tactile feel of the pad but also the driver behind it.
The keyboard is also excellent, very responsive, light, precise and accurate. I dont think I've missed a keystroke yet that I know I pressed, which is always one of my biggest bug-bears.
The chassis is also good quality although I'm not a big fan of metal in portable devices (it does not bounce), it does the job well and the size/strength/heat-dissapation is great.
The main reason I ditched the 2007 MBP was due to the god-awful silver keyboard and the trackpad. Both of these have been upgraded in the unibody macs and because I am now becoming less dependent on Windows software, 2014 was a good year for me to try it again.
I have to say after several months of using my rMBP (w/Yosemite), I have not had one single issue and most importantly the machine is a joy to use and there are no annoying minor irritations at all which means I can use it for extended periods without any nagging doubts about which bit I would improve. That in itself is worth the extra expense for devices such as these.