I thought I would take a minute to review the ubiquitous Clarke Super 7R hardwood flooring edger.  This venerable machine has been in use for decades by flooring professionals and rental yards.  If a tool can stand up to the DIY'er crowd you know it's tough!
The Super 7 can be distinguished from Clarke's other primary edger offering, the B-2, by its shorter housing and lower rpm rate.  This slower rotation makes the Super 7 less aggressive in the hands of your typical novitiate but the slower speed is also useful when removing coatings that tend to gum up sand paper.  
These machines cost about $1800-2200 and have a long service life.  However they do require regular maintenance.  It is often necessary to replace the power switch, repair broken cords, replace the light buld, remove and replace the sanding pad and most importantly to make sure the commutator does not spark or produce heat.  The commutator can usually be rebuild for around $500.00; certainly preferable to buying a replacement.  Check out  http://www.greenpointefloorsupply.com/ for an excellent resource for parts, service and materials.