Of course futures. Like one of the poster said, you pay less tax on it. Of course, if you are a net loser, it doesn't make a different. The spread on most semi active and active futures is 1 tick. In additional, futures has another benefit, you don't need to list every freaking transactions like it's requires for stocks. Assume you semi-active, say 100 a transaction a month, that's 1200 a year, that's a lot of lines to enter on the schedule D. Software help, however, you still have to review each transaction, because the import could be mess up.