I would say that going ura is safer in the sense that its harder for uke to hit you. For example ai hanmi ikkyo, if you go ura when entering its almost impossible for uke to hit you with a punch with his free arm. If you go omote and donīt do i good enough maybe uke can hit you.
But if you donīt know what attack uke going to do i think itīs safer to go omote. In randori for example i almost always go omote and use atemi to protect myself. The reason for this is that if uke for example raises his arm and you think heīs doing shomen uchi and you start going ura and then he does yokomen uchi instead you are actually moving in to the strike... OUCH!
Same with tsuki. If uke does a hook instead of a straight tsuki.
So for a real life situation, where you donīt know whats coming at you I think it would be better to move omote.
By the way, you can always enter omote and then do a ura technique...
Just MY opinion.