I was reading an old article from THIS IS SPENDAAAAAAAAA yesterday and saw this:

Quote Originally Posted by spenda
Tilt Control – Phil Ivey

This may surprise those who do not know it, but Phil Ivey is the king of “stop losses” online. Ivey refuses to play after losing a certain number of buy-ins which can be as low as two. This commitment to only playing when winning is a big part of why Ivey has been the number one earner in online poker history despite playing about 10% as much as players such as Dwan, Galfond, and CTS. Ivey does not succumb to tilt, he merely turns off the computer and comes back at a different time when he is more focused.
Taken from: Building an Unbeatable Poker Player

Your stop loss sounds good to me