Aluminum suck! That is what we have for our work trucks and we replace them all of the time. The cross supports break when off road due to flex. I have had a fiberglass one for a while and it is very useful and holds up well even with a canoe on top and very rough rocky roads. I would say the most sturdy ones are LEER and ARE. LEER will put extra support inside the fiberglass if you want. I got mine for $1000. I see them used for much less all the time.