i wouldn't mind some suggestions because i can't find anything at ~£30 that is significantly better. the noctua ones (d14-15) are about ~£70 and don't seem to worth the extra money. at that price i might aswell look into an AIO which are ~£100 for the popular corsair models.
my 212X is just fine with my overclocked 6700K (1.34V which is quite high) which is averaging about 20c browsing the internet/streaming music. during games at 1440p 60fps with only a few settings lowered in most games (gta v, the division, watch dogs 2, es
, doom) it's usually anywhere between 50-65C but can sometimes spike to 70 here and there. during video editing the highest i've seen it was 73C. under heavy stress tests like prime95/ibt after about an hour it does 75-80c. of course it's not as good as liquid cooling but not bad for £25.
see above for my experience with the 212. there isn't much a difference between the 212/212X. it's just a slight update. the 212 is still a great choice for the price. if you really want to heavily overclock then i'd say the money is best spent on an AIO.