Perhaps unsurprisingly, I prefer spouted to bottomless, even though I have both. Once a coffee is dialled in then presuming you are using same bean, grinder, machine, tamper, RDT tool, WDT tool, paper filters, metal screen, spritzing bottle then what are you checking? To me, the cleanliness argument is a very weak one. Who changes their bedding after a single nights sleep but if I argued to say that all those disgusting body fluids and skin contaminate the bed and bedding could you really argue against that? Like so many things in the world of coffee bollox, you can make an argument for just about anything. Cleanliness of a pf…..you are drinking what goes through it! A good chef never washes his Yorkshire Pudding tins