I run 64 bit Windows 7 and now I know why only certain programs show up for deletion. I sometimes wrangle with the same question. Is Revo really needed ?
In my dealings with Revo, I can only say that there are ALOT of files, registry entries etc, left over after an uninstall. So many that I was astounded by the sheer number
of entries presented AFTER the program uninstaller ran. So far, I've had no problems deleting everthing Revo has presented. YMMV for sure.
I suppose what bothers me most is "Why programmers won't, or can't, write an uninstaller that actually uninstalls their program. I understand shared files. Thinking back to several programs I Revo uninstalled on a 32 bit XP Home machine, I would guesstimate a couple of HUNDRED registry entries would still remain without using the Revo uninstaller.