it's only just slightly less than half your standard 5 gal homebrew size.
but yes at this size, 1 gram of 6%AA hops equals about 1.5 IBU's so i would have to be very careful with my weights in both grain and hops. but i dont see why this couldn't be recreated on my two bigger breweries... granted there may be a very slight change... but the pallet can't taste the difference if it's within 5 IBU's when it comes to bitterness.
I'm mostly doing it because i want to be able to mess around more with ingredients and flavours, without spending too much ( i worked it out to be £3.83 for my most expensive recipe on this system), and also i wont waste much if i make a cock up and produce something distasteful. i also will be playing with mash rests and and temperatures, then comparing how different mash rests affect the flavour... my only other brewery that's scheduled for a herms system is the kilderkin... and i dont fancy spending £50 on ingredients and having to pour 85 litres down the drain if i feck it up :?