Isn't the ETF, "SSO" living proof that leveraged ETFs can be bought and held long-term?
from tis inception in 2006 to present, SSO outperformed SPY by a significant margin.
(not by double, but still outperformed).
so if it could withstand the infamous crash of 2008 and still come out ahead...
it can probably withstand almost any kind of conditions. yes?