Bugger all ... I'd have thought.

Charles is ALWAYS impeccably groomed (if a trifle old~fashioned) for starters. Whereas, Ozzy ... ... ? 'Nuff said, really!

- and their respective appearance - apart though, the pair do, in fact, share some similarities as listed in the following link I've come across:

http://www.bbc.co.uk/news/technology-37307829 ...

Ozzy does, however, look younger ... as well as a bit less careworn than Charles.

... judge for yourselves!