The reason I'm going for an i5-9600k is because it gives me good overclocking capabilities. Also, most importantly, I like to play x Plane 11, a flight simulator, which is very much a more cpu intensive software. In this, clock speed is more important than hyperthreading or core count, and on a budget they recommended the i5-9600K. I've been closely monitoring the price of this cpu for a while and it seems I can get it for as low as £150 on amazon