Often we will waste tremendous amounts of time debating a choice between alternatives. Where to have lunch, how to implement a feature, how to model some data, blah, blah, blah, ad nauseum.
Funny thing is, we usually don't get into debates like this unless there are compelling arguments on both sides of the issue. The more heated the arguments, the more likely it is that either alternative provides near equal utility.
In these cases, you might as well flip a coin. Make an arbitrary decision; move on.
Similary, don't bother defending the alternative you chose under such circumstances. You made a choice because you had to, not because you had a clear superior alternative. If you could have defended your alternative, the decision wouldn't have been arbitrary.