re: BOIL has become predictable

Would be subject to some extent to both contango and backwardation. Here is what they hold:

LINK

Without typing a novel, and based on the above holdings, they are obviously more stable with respect to tracking actual price as compared to one of the 2X or 3X instruments. The credit risk would be significantly less here as well. It's not a note. And the roll, and roll date are always mitigated as it holds the prompt month.

The next most stable in my opinion would be UNL becuase it would track a 12 mos rolling strip.

I've always maintained ETN's as opposed to ETF's are for traders, as are all the levered instruments. But I'm pretty conservative.