I actually started out just going to the docks with a weighted (to help it sink before its full) 5gal bucket on a rope years back. I would go to the end of the dock, dip it full, pull it up, carry it to the 45gal rubbermaid container, dump it in and repeat untill it was full.
I had great results from this (now that i think about it, maybe my best results), but i was convinced by LFSs that I was poisoning my tanks and I wasnt giveing them adquate minerals and things etc. So, i jumped on the instant ocean band wagon and have been there ever since.
Now, seriously, for $.05/gal, it would actually be worth the money to me to avoid the extra effort of carrying the bucket back and forth. I supose haveing the water drawn off the bottom would be much cleaner as well.