I understand that even the bests of everything we do would probably be inadequate for doomsdays. There is always something that we missed. It is that something that does us in.
We can try to be redundant, triple-redundant on everything... trying to save us. But we also have our checkbooks to protect. Everything sounds fine and dandy... backup power, RAID, multiple internet feeds, multiple brokerage accounts, cell phone + landline, etc.. But when the price tag is revealed... things don't look that rosy any more.
However, volatile markets are not that far fetch. I have experienced one, in 2008. And many of us here saw what happened during that "Flash Crash" in May 2010. We can never be too prepared. But it doesn't mean you shouldn't do something to saveguard yourselve. You need to balance between how much protection you seek, and how much money you can afford to spend on such protections. Kind of like buying insurance policies. You can't justify the spending, you walk away and take the risks. I understand that and respect that.
To me, picking an i5 versus i3, with minimal money spent? That's a no brainer. Why buy something that is only marginal? Only because we haven't seen the volatile markets come back since 2008? You know... when the Iranians fire a missile at Israel, or the North Koreans at USA, or a dirty bomb set up in San Francisco... they ain't gonna give you a 5-day notice so that you can upgrade your equipment to prepare for it.