To me a true all-rounder is someone who can make into the team both as a batsman and a bowler. Sobers definitely could, but Kallis? I don't think he makes into any current test team as a bowler. (Of the past all-rounders, the only other who could easily meet this criterion is Ian Botham.) Shakib should be able to get into any test team as a bowler. As a batsman, he should be able to make it to at least half of the test-playing nations. I don't expect him to attain Sobers' level, but he should be able to get close.
প্রথম বাংলাদেশ আমার শেষ বাংলাদেশ, জীবন বাংলাদেশ আমার মরন বাংলাদেশ।