I've looked at those before... but i just can't justify with myself spending that kind of money when I can make my own for about $50.
If I were to buy one, i would definitely buy aluminum though - that thing will last the test of time. Where are you planning on putting it? I think I can get my bro-in-law to make me one that will fit into my rear bench out of aluminum (he owns an HVAC, so he has all this aluminum and the bends and crimp machines). the only problem I have with that is where i would put the person in the back if anyone ever fished with me. I guess I could always put a pedestal seat with a long pole in the floor deck.