which one is better DIA or SPY and why?
You could buy DDM double % dow longor dxd ultra short.Wanna get even more juice?? Buy options on these
SPY is much better and the bid/ask spreads are typically much lower on the ETF and the options.
To judge whether SPY b/ask spread is better than spreads on SPX, you have to multiply it 10 times and then compare.
doesn't matterMarket goes up both will be worth money down they lose. Whats the question?
Which is better for what? In what terms? Give some details of what you are looking for.. long, short, call/puts, spreads, straddles, condors, etc. Then I can answer your question :)