If I had faith that nothing would ever go wrong or that the worst case scenario was impossible, I wouldn't bother PGP encrypting my address, yet that's my biggest message on the forum (check my sig). Even if the worst case scenario doesn't happen, lots of other things could go wrong. Perhaps you remember the November down time when people's accounts and money were inaccessible for 5 days. That is reason enough not to store more coins in your SR account that you need for a purchase, and no longer than you need them for a purchase.