As the cartridges (200ml) are 79 pounds each, that's 869 pounds to replace them all - with Epson inks.
I use a large printer too (though a much older Epson one) and I find that, as long as I switch the power completely off (not on 'standby') I don't have a problem with clogging. I'm just a hobbyist too - mainly making prints for photo club competitions etc - so I don't want to even risk a whole set of Epson's (genuine) inks. So I go for compatibles. While I don't suggest everybody should do the same, it's worth doing the calculations for yourself. An Epson 220ml cartridge would cost me $149 each (in Canada), while the 'compatible' one is $24. A no-brainer for me - but not necessarily everybody.
Bear in mind that, when you do a 'Nozzle Check' you'll be using quite a lot of ink - and paper too!