What do you want to see of out this momentous interaction?
One, I would prefer if these two didn't pick each other apart. This is Superman meets Superman, they should admire each others differences and point out the strengths of one another. It should be a friendly meet up, with Pre-Flashpoint Superman giving his condolences to the current Kal-El for all the things he has recently had to go through.
Maybe in a follow up issue, one that doesn't already have so much going on, they can compare stories. "Let me tell you about my Parasite" "Well, this is what happened with my Doomsday" etc.
They should each have a bit of curiosity at each other's choice for a romantic partner, but no opinion either way.
New Earth Supes: "Lois, huh? Looks like things really worked out for the two of you."
Pre-FP Supes: "Don't think the thought of being with Diana never crossed my mind, I'm sure you two will work it out."
Basically, I want to see supportive interactions between the two.
What about you guys?