I think the 13-inch rMBP (with 16GB of RAM) is a pretty bad-ass machine. Yes, I love the tricked-out 15-inch rMBP with dedicated GPU, love it -- but if you have to be portable at all, it really does add a lot of bulk. Now, if you are mostly plugged in, that plus a nice 27-inch monitor (Thunderbolt Display or a 4K screen, depending on what you're doing) is awesomely badass.
As for Windows-based alternatives, you can custom configure some to be quite good, but you still face the software issue. Still, of the best Windows laptops I've tested in the last year, the Surface Pro 3 is quite good. It has a built-in pen, the only shame is that Wacom no longer does the input and as a result, it isn't quite as precise (with pressure points anyway) as it was when Wacom did it. Still works quite well and Photoshop CC 2014 support is coming.
Some of the higher-end Zenbooks are good too.
Still, for my money, I'd get a rMBP, with 16GB of RAM. You can find ways of upgrading the hard drive after the fact (OWC sells aftermarket SSDs), but the RAM is soldered in at time of purchase. Go ahead and max out now. That'll especially come in handy if you're dealing with massive Photoshop, InDesign, Illustrator or Sketch files -- not to mention if you get into any motion graphics.
I think the 13-inch rMBP (with 16GB of RAM) is a pretty bad-ass machine. Yes, I love the tricked-out 15-inch rMBP with dedicated GPU, love it -- but if you have to be portable at all, it really does add a lot of bulk. Now, if you are mostly plugged in, that plus a nice 27-inch monitor (Thunderbolt Display or a 4K screen, depending on what you're doing) is awesomely badass.
As for Windows-based alternatives, you can custom configure some to be quite good, but you still face the software issue. Still, of the best Windows laptops I've tested in the last year, the Surface Pro 3 is quite good. It has a built-in pen, the only shame is that Wacom no longer does the input and as a result, it isn't quite as precise (with pressure points anyway) as it was when Wacom did it. Still works quite well and Photoshop CC 2014 support is coming.
Some of the higher-end Zenbooks are good too.
Still, for my money, I'd get a rMBP, with 16GB of RAM. You can find ways of upgrading the hard drive after the fact (OWC sells aftermarket SSDs), but the RAM is soldered in at time of purchase. Go ahead and max out now. That'll especially come in handy if you're dealing with massive Photoshop, InDesign, Illustrator or Sketch files -- not to mention if you get into any motion graphics.