Not the same.

Almost everyone but ragers can buy flight potions; many, many people feel prohibited by their role-play from paying centurions.

Trip only prevents fleeing for two rounds; centurions prevent fleeing for the duration of combat.

You might retort that one doesn't have to fight centurions, or doesn't have to fight Imperials while at centurions. This is fine, except for raid and retrieval situations, where it's pretty much mandatory. The problem is compounded when those cents have black shroud, and there are multiple Imperials ready to spam curse or damnation once you initiate. That's assuming your class can even word from combat.

Now suppose you have to go through at least two sets of those, with multiple defenders waiting to engage each time you start on a pair.

Even outer guardians (including the Vanquisher) can't block fleeing as effectively as centurions do. My personal opinion is that cents' "flee blocking" ability should be on-par with outer cabal guardians.