Not wanting to risk throwing an unstable economy down the river on the off chance that it might be better, with no guarantees or figures? That's not a valid reason to leave!
How about if I said to you that if you give me all your money, it might be better for you in about 15 years? I won't tell you how I'm going to do it because I actually don't know myself, but it'll definitely be better than what you've got now. You'd think I was absolutely crazy and tell me to sling my hook, and you'd be right to do so. The pound already slumped yesterday on the news of the referendum and the possibly we might leave given the opinion polls and the power of Boris, exactly what happened when it looked like Scotland was going to leave the UK. That uncertainty is only going to get worse, and the markets will fall over again.