it all depends
on how much you want to spend (sorry I meant fly - but they are mutually linked). For me, with the amount I fly, it just about works out less costly to hire.
There is also a line of thought that says that renting MAY lead to less potential hassle. The planes may not be so tidy BUT, when you are done, you walk away and dont have to worry about the internal group politics, maintenance or potential for someone bending your share of the metal..
However, the minute you want to regularly fly more than 2 or 3 hours a month, over longer distances and perhaps with overnight stop overs, it appears the equation changes radically. Renting does not make sense.
So I come back to, how much do you want to spend ?