Question I7-7700K/Asus ROG Apex/ memory and CPU cooler advice

Dec 25, 2019
Earlier a good suggestion for the unopened I7-7700K CPU I have was the ASRock Fatal1ty Z270 Gaming K4 ATX LGA1151 Motherboard, this versus the more expensive Asus Rog Maximus IX Apex. MOBO options are now slim for the 7700K.
I now have another desktop PC for workhorse stuff, OC holds some fascination (been out of all this PC building for a while) and the Asus Rog Apex has a Canadian price and free shipping from whereas the ASRock has a US price and shipping cost and also looks unavaible as new right now. Although still more, not a big difference in cost so i am going with the Asus Rog Apex.

So what memory would everyone advise? For regular and also OC.
I am thinking Corsair Vengeance LPX 32 GB DDR4 3600 -can it use 3600 or even more?

For water cooiling what has the best reputation?

My other option is to sell the unopened 7700K and go with 8700K/9700K/Ryzen ...but maybe not.
Thanks for your help.