Couldn't find a decent Royal Commercial on CL, so I went to my local vac shop a few weeks ago, prepared to lay out four-plus bones for a new one. (Got my others there). He didn't have one in stock, but had a PRISTINE kiRbY Ultimate G, just taken on trade he would take two out the door for. Considering my aunt just paid almost $2g for a new one, figured I couldn't go wrong.
After many years of dissing Kirby, I gotta admit I like it, as does my helper. The only differences I can tell between mine and my aunt's new one are cosmetics, and her handle locks upright.
Just minor issues with my old Royals, after thirteen and ten years each. Lots of "beausage". I'll fix them to like- new when I have time.
Advantage of Royal Commercial over Kirby: Lighter weight. Longer cord. The true, ten-amp, Commercial models may be a little more powerful than the seven-amp Kirby. Can't really tell a difference in performance. Not all metal Royals are Commercial models. Some metal Royals have six or seven-amp motors and lighter, shorter cords.
Advantage of Kirby over Royal: Self-propelled, slightly bigger bag, accessories. Made in USA. My old Royals were made in Cleveland. New Royals are cHinEse.
Accessories are, or were, made for metal Royals, but are difficult to find.
Trivia for anyone who cares: Kirby is a Birkshire Hathaway (Warren Buffett) company.