When my 2008 iMac went up in flames (quite literary!) following a succession of other costly hardware repairs I designated my mid-2011 MacBook Air as my main machine. It only has a 1.6 Ghz Intel Core i5 processor, 4 GB of RAM, Intel HD Graphics 3000 and 128 GB of SSD storage. But it absolutely flies-along and has no issues whatsoever running both RW7 and RW8; and the huge project files you lot often send me to troubleshoot!
I would imagine any newer or more spec’ed-out MacBook Air would work just as well or even better.
Obviously I have an external monitor plugged in, a decent sound system, wireless keyboard, keypad, mouse and various other accessories. To combat the virtually non-existent 128 GB internal storage, I invested into a Western Digital Thunderbolt Duo external drive system - which gave me an extra 4 TB of RAID-1 secure storage to offload all my big files and backups onto. This whole setup has worked adequately for me, for nearly 4 years.
In that time I have saved-up enough to buy a Mac Pro and at least 2 cinema displays. But Apple’s hardware offerings are so woeful for the expert market right now, I am “making do” with what I have for as long as possible. I prefer the reliability and flexibility of a modular setup that I can ‘custom build’ myself. The iMac was a lemon and I can’t see myself going back to an ‘all in one’ configuration, after all the grief the last one gave me.