One problem with the checkcalling line is that you are just asking to get blown out of the pot to a huge bet on the turn or river. I think the checkraise is a far preferable line because it represents a lot of strength on a flop where you are either way ahead or way behind, plus it gets the weak continuation bet when he folds. You can also get better hands than yours to fold: depending on the player and your image, as high as AA or definitely pockets lower than 10s. It would take a rare and ballsy player to reraise your 20 checkraise on an A high bluff, and usually you can spot those players with reads (or know your table image is wild enough that people will play back at you so strong and adjust accordingly). In my mind, checkcalling this flop is very weak, and if I have AK against you and I've been playing tight and generally making continuation bets (meaning it's more likely you'd call my bet on the flop, hoping I have exactly what I have with your middle-strength holding), or if I've seen you make some loose and questionable calls, I'm going to make a sizeable bet on the turn (3/4 pot) a good percentage of the time and you're going to want to vomit with your pocket threes.