Obviously there are a plethora of variants but, comparing apples with apples, they are both solid aircraft. So, if you were to look at a 160HP 172 and a similarly powered Warrior, you would find that operating costs would be similar. As far as flying them is concerned, they both have similar performance. AS VH says, it comes down to personal preference. Mine would be for the 172, but that is purely subjective.
You can't go far wrong with either type.