Several things aluminum has going for it over carbon.

They are easier to work with. If you've got a bad insert, you simply heat it up and remove the insert. With carbon, if you've got a bad insert, you've got a much bigger problem. Depending on what glue you've used, it's either a royal pain or impossible to remove the insert without fatally damaging the arrow.

Aluminum arrows might bend, but the problem is like so-o-o many others in the bowhunting market these days. Blown way to hellngone out of proportion. Not to mention that if something can bend, it can also be straightened. With a straightener and a little practice, most bent aluminums can be brought right back into factory specs. As long as you haven't put a 'J' hook into the arrow, it can be straightened.

And then tolerances on aluminums are so tight that carbons can't compete. Near perfect consistency in weight, spine and inside diameters (no sloppy or too tight inserts like with carbon). Easton has been making aluminum arrows since the 1920's and they've got all the bugs worked out of them. Carbon? Still a work in progress.

The only two things carbon has going for it are strength and light weight for speed and flat trajectory. Durability is often thrown around as a major benefit of carbon but that's only when comparing aluminum arrows of comparable weight. Those thin walled beer can arrows are definitely fragile. Go up in weight into arrows with wall thicknesses of at least .015" and I think they are just as durable as any carbon on the market. Their only problem is they're much heavier and don't fly fast enough to suit the speed freaks.

If your dad is happy with aluminum, then leave him be. Maybe if you shut up and quit badgering him about it, you might learn something from him. Believe it or not, he just might know something you don't.