the company i work at gives us all this exact choice, and these days most of us go for the Air. personally, i prefer the portability and the extra battery life. for me the retina display is a bit of a gimmick, and to be honest i think almost everybody's whose had a retina MBP here has experienced catastrophic hardware failure at one point or another. apple always take pretty good care of you when this happens, but it's better if it doesn't happen at all. who knows though, maybe they're issues that have been sorted out now.

but yeah, i find my air is more than adequate for all the stuff i do on it (basically the same as what you're asking about).

I do similar work so I guess I can chime in with my experience here.

I went from a 2011 13" MBA to an early-2013 15" rMBP and found the difference to be massive. The main benefits being the incredible display and a pretty decent cpu/gpu/ram upgrade. After using the retina for a couple of weeks I opened my MBA (which was gathering dust on a shelf) and couldn't believe how bad the screen looked in comparison.

However I do miss the battery life and boy does this thing get HOT. It's summer here in Brisbane and yesterday (it was around 35c) my CPU got to 106c.. my lap did not enjoy.

But yeah I definitely recommend the retina. Be sure to max out the RAM too.

Edit:

I recently added a 27" haswell iMac to my collection which was another massive improvement. I've been doing maintenance on an old node.js app that has a pretty crazy build process and compared the runtime on each of the machines - The MBA took just over 3 minutes, the rMBP about 1.5 minutes and the iMac did it in under 20 seconds! I still spend most of my time on the MBP though :)

It's not a good idea to use a laptop in your lap for extended periods of time... expecially if it's running at 106C... especially if you're a male.

Rails? MBP or better, for me. Running unit tests on the Air kicks my fan on and takes many seconds just to start up the harness. You need to think of available RAM also, if you're using a fat IDE like Eclipse or RubyMine.

A way around this is to simply SSH into a bigger box to work on. Then it's GREAT. If you use Fuse w/ SSHFS, it's powerful enough for a fat IDE... but I still use TextMate or Vim over SSH and run my tests on command line remotely on the Air. It saves days of productivity.

Which year Air do you have? When I fire up a Rails test suite on mine (hundreds of tests, many with JS through poltergeist) it doesn't stutter or enable its fan.

After a lot of back and forth I went with the late-2013 15" rMBP and I don't regret it for a minute. I know, it's expensive but if you can afford and as someone else said here, after you spend some time with the retina display it's hard to get back to a non-retina display, I can tell you that for sure, especially when you work on the high-resolution ratio...you can fit a lot more content at that resolution and is quite useful when you design.

Air.

I bought the Pro for web development and I think it was a bit overkill. I don't really use the Pro-ness of it ever. I think the Air is a better deal.

I don't quite agree with the much lighter tag with the new retina macbook pro. May be this argument held well for the old MBP. The new Retina MBP is 1.60 kgs compared to Air which is 1.35 kgs. I personally moved from Air to MBP just because of the extra power and I did not notice much on the difference in weight.

I do a lot more Nodejs stuff than Rails, but I’ve gone from a MBP to an Air, mostly for the battery life. It’s done quite well for everything, including Adobe suite.

One thing though is you can forget trying to run dual monitors on an Air if you’re into that.