Uninstall HDM 2010/Install HDM 2011 question

I uninstalled HDM 2010 and installed HDM 2011 but forgot to delete the old version's folder first. Does it matter? Can I delete it now?

 

I uninstalled HDM2011S to install HDM2011S SP1 without doing anything else also and restored an image 8/9 times with no problems at all.

 

If you want you can delete the old folder & any Start Menu shortcuts left behind.

HDM '10 & '11 include 3 files that may go into Windows' system folder, if they're not there already, + the Hotcore driver... if the '11 versions were newer they should have overwritten the existing copies. Everything else, i.e. the files in the program folders are self-contained, so what's left from one should have zero effect on the other.