Actually, the real draw to me is that sidechains are an approach to NOT changing Bitcoin.
The beauty of it is that it can be said both ways. To me locking my bitcoins and switching to a side chain means I change/fork
my bitcoins.
The danger of it, on the other hand, is somewhat akin locking your gold and getting nice pieces of paper in return.
That German gold is still locked there somewhere, maybe...
I absolutely won't be using sidecoins that offer me only such a thing. I don't have any paper-gold either.
I want strong and well researched crypto that allows me to be sure that I can exercise at my own digression any of the contract terms I agree to.