It depends on how you look at it. As a bts holder, the price fluctuates wildly. Up to 100% the past days. But when you switch to the usd point of view, it is fairly stable. Hero is by design stable to reflect 1913(?) value of usd with a 5% yearly increase.

If you sell lower than you purchase, you allways loose. There is no difference there. But the way the hero is created, adds another risk. The hero is created by locking up bts. And if the collateral gets less value than you agreed, you will loose all of it. It is a nifty system that will make the supply of bts shrink.

I don't recommend doing this because of the risk of losing everything. It is another matter if you are a usd holder and use it to buy hero. At least on paper it looks like a much better deal.

My personal point of view is that bts will gain the most and holding it at least for a few months will probably be very good. Especially if this challenge is successful. But taking part in it? No. It is a high risk game. And I value my sleep much more than risking my bts.