Well, you really have to figure out how much it would cost your site/service to be down for 2 days straight. Or maybe a week (PSN). Would this design pay for itself in preventing that loss?
...and then multiply that cost by the probability that this will happen to find the expected payoff. If the work costs substantially more than the payoff, don't bother. If substantially less, you're negligent if you don't do it. (The Learned Hand Rule http://aler.oxfordjournals.org/content/7/2/523.full)
