C02 buckets any good?

http://cheaphydroponics.com/store/co2-equipment/co2-boost-system/prod_537.html. I was wondering if anyone has used these and if they are worth the money. Looking for a cheap hassle free way to boost my C02 levels, any suggestions are appreciated

put some yeast and sugar in a bucket of water and use an airstone with a pump

I cannot convince myself that they will raise the CO2 appreciably
when I am ramming massive amounts of air through my tent.

In a sealed env, they ought to rock.

Just my $0.02

JD

these look cool:
http://www.thegreenpadstore.com/Products.php