theres more than just ROM manager tho..theres GooManager(beta) and Romtoolbox. ive used goomanager for rebooting into recovery withut having to turn off and do the finger shit and installing the latests gapps.
ive used rom toolbox for loading up boot anis, build tweaks, speed/batterytweaks, backing up apps, reinstalling apps(saved me loads of time when flashing back and forth from cm7 beta to my backup) and just about everything else. but, ive never flashed a rom thru them yet, havent looked to see if its safe.