Na cheaper than £120 na not a good idea and the 8700k will be short lived on z370 anyway add to which the 8700k when oc'd to 5ghz consumes 145w+ and those extra cores and threads are wasted and not needed for gaming, now that zen 2 is out intel will push z390 faster and there 8 core to take back the top spot, nuking the z370 in the process. This way I get a high end board big overclocks while staying around 100w and not wasting any of the chip, also worth note that due to the extra cores the 8700k's chip latency is a touch higher, every bench has the 7700k up there in gaming still managing to steal the top spot in some cases. The only problem is until recently very few people pushed ddr speed and timings all of which came into the spotlight with ryzen, not many will have been running a 7700k at 5ghz with 4000mhz ram, and tight timings showing even more extra perf on the 7700k. Besids z370 is just a z270 rebrand it adds nothing in-fact even the imc in both chips are the same as is the ipc, if I wanted cores and threads I'd go ryzen not a 12 thread intel that's about to be nuked, but thx I do know you really like intel though.
I'd still suggest going for the 8700k and buying a cheaper motherboard...
Still easy to delid and oc a 7700k with fast ram & tight timings, your not running into any bottlenecks any time soon and you gat a very fast general pc that will do anything except render, nobody apart from renderers need more than 16gb let alone 32gb, plenty of pci slots, dual m.2, power/reset/debug/ln2/dual bios/solid vrm effective heasinks, £120 lol easy.
Yep, good for those looking for a board upgrade though
Are you serious lol