You need to look closely at precisely what is being guaranteed. Your five-9s and mine are two different things. Companies get ripped off all the time on HA stuff because they don't understand exactly what they are really buying. five-9s don't do you any good if there are three-9 caveats in the system. The weakest link and all that. You see this all the time in the networking business; MegaCorp buys a nominal five- or six-9 telco circuit, but small parts of the entire system are three-9 grade (something the telco never advertises or mentions, though one can infer it by very careful reading of the contract) and so the entire circuit is effectively three-9. Same with big HA servers, excepting some of the truly stratospheric non-stop systems you can buy from IBM and similar.
Incidentally, I pay next to nothing for five-9s. It hardly costs anything if you have experienced system architects instead of goobs in suits designing your systems. I don't buy the stratospheric mainframe systems. In fact, just about everything mission-critical these days is fancy PC hardware.
Basic hardware failures are a giant red herring. Any reasonably designed system can deal with those. It is the software failures that kill you no matter how bulletproof the hardware is. And throwing money at the hardware generally doesn't solve the software issue. Which was my whole point really (well, other than that the UNISYS system is a dog); no amount of hardware will save you if the software isn't just as bulletproof.
So, how many nines do you get on all the software that runs on the ES7000? Read the contract carefully...