Reaper's multichannel WAV support makes comping multitracks a breeze.
I really like Reaper. I've been using it since 2007, way back at v1, and while I've flirted with other DAWs I always come 'home' to Reaper. But if I had to pick something I'm not 100 percent happy with, it would probably be the take-management and comping facilities. Don't get me wrong, comping is by no means terrible in Reaper — it's perfectly workable for simple mono/stereo sources like vocals or guitars (as covered by Mike Senior in SOS April 2011: www.soundonsound.com/techniques/comping), but once you start getting into anything over a single track things can get very fiddly, very fast.
For a start, the timeline display can get messy. Reaper's take visualisation isn't the prettiest at the best of times, but once you start comping a large number of tracks, each with several takes, the visual clutter can become overwhelming. Check out the first screenshot (above) and you'll see what I mean.
It's not just an aesthetic issue, though. Track grouping doesn't include take selection, so while you might click to change to take three of your kick drum, all of the other drum tracks will stay resolutely on take one — until you manually go through and change them. Not only is this laborious, but it's all too easy to get yourself into trouble, and end up with tracks assigned to different takes. In some instances that might be creatively desirable, but for something like a drum kit recording you really want all the channels to stay in lock-step with one another while comping.
My initial workaround for this issue was to eschew 'point and click' take selection entirely, and just step through the various takes using keyboard shortcuts. With items grouped, you can step them back and forth through the takes using...