It is cheaper, but you use more. I just like the fact that I fill up every week/week and a half on 98, if I'm heading to the petrol station more often, in my head it seems like I'm using more fuel/ spending more money lol.. Plus if you've got the hardware already for it it makes it easier, plus a retune.. I guess it'll be like gas, a decent layout (surge, pumps, injectors, retune, lines) for some more than others, but cheaper to run'ish...