In the modern era, I'd say he was the best, especially as an entertainer. The old pro's like the Davis brothers, etc, couldn't live with him. Could have the two Steves given him a game........well, that's like asking if Louis could have beaten Ali....different era's.
Hendry and O'Sullivans carears have over lapped and Ronnie holds a 30-21 head to head winning record against Hendry, though Hendry as won 7 worlds to Ronnie's 5, Hendry as won 5 uk Champs to Ronnies 4, he also leads in The Masters by 6-5. They've had 11 maximuns each, so all in all pretty even.
so far.......