I had the same dilemma. I ended up with the 233 mainly because of how it sits on the wrist and it works better when you wear a suit.
You really have to go in and try both. before I tried them I was 90% certain that I was going to go with 312, but after I tried it on and saw the doomed crystal, I was sold on the 233 dot.
Also, it's a pleasure to wind the 233 once a week!!