[kspaans]

I've heard that leveraged funds aren't great as long-term vehicles[0]. Even the summary of TQQQ says this:

Due to the compounding of daily returns, ProShares' returns over periods other than one day will likely differ in amount and possibly direction from the target return for the same period.

Though if you are into market timing, they seem cool.

0 - http://canadiancouchpotato.com/2010/01/26/the-trouble-with-l...

EDIT: formatting

[choppaface]

Yes, and there are some volatility issues too-- the price of the ETF/ETN can fail to follow the target in cases of scarce supply/demand.

Agree that it's most effective to buy at the bottom of a crash. E.g. see SVXY Feb 2015-present.