Thank you for the responses friends. looking to case it all into a NZXT H440 or a Phanteks Enthoo Evolv along with a 1700x + gtx1070 setup. i believe i won't get as much of a benefit o/c water vs air-wise with those parts compared to other higher spec'd items but as metioned, have that hankering to build something watercooled. *bucketlisted was only looking to do the CPU for now but will eventually move to both GPU as well. (unless that's bad to have mixed? liquid-cpu and air-gpu) did read up about the aluminium mixed compound kits but noticed most kits in that price point (rl240) are all aluminium alloy/mix. the radiator has zinc as stated above but the ek-Supremacy block is also an aluminium faceplate (please correct if wrong, but the whole ek fluidgaming kits are all aluminum alloy?) also was originally leaning towards the thermaltake kit as it looked the most user-friendly to setup and the w1 block has the am4 bracket like the fluidgaming ones. still weighing up the options at this stage so i don't stuff it up so i appreciate all the input.