I typically use RM when I am just flashing something that does not require a wipe (kernel, theme, etc), mainly b/c it is easy to select it from the list and it will reboot automatically after it finishes. If a wipe is required then I will do it manually, I got used to having to wipe everything 3x b/c RM would not always clear everything up and screwed up some installs.
The best reason to use RM is for backups. I am kind of OCD when it comes to naming conventions so I keep my backups pretty well organized. I like to know when it was done, and what it entails. My first backup of the bionic was 0924_Bionic_stock_noapps, pretty self explanatory. Again, reboots after its done.