I believe there's not a right/wrong decision there.
In my case, I wouldn't let my 5164A go for any other Aquanaut. Perfect proportions on my wrist, comfortable and versatile like hell, useful complication, sporty enough to take it to the pool in summer and classy enough to wear it with suit and tie on a daily basis.
But if you prefer something sportier and you don't really need the travel time function, then 5968 is your watch. And it's new and kind of hotter nowadays, which some people value as well (not me).
If budget allows, 5968A and 5164R is a killer couple π