Cech made 70 apps for Rennes (wiki) enough to judge how good a keeper he is. It is also not strange to see keepers move from smaller teams to much better/bigger clubs and get games, more recent examples are Lindegaard or Courtois. While Sturridge played 12 games for Bolton, and tbf i didn't have time to watch like 8 of those games, but the few i saw he did not play as a lone striker like he'd be asked to do here. His positioning is alright, his finishing decent and pace great, but there's more to it than that. In the 1 game he started as main striker for Chelsea against Blackburn he had a tough time shaking off Samba and Torres was brought in at half time if i remember correctly. People who expect him to just step in and instantly shine could very well be wrong, but we will all see... eventually.