Ummm.... that's ironic, your questioning relevance ? Did you read the OP ?
1. The OP didn't ask for an adequate cooler, he asked for the "best cooler".....the words "best" and Hyper 212" can not be used in the same sentence which I think should be obvious given the 14C spread...... between the four numbers ..... 65.75C, 51.75, 52.25 and 52.5 which of the four is "relevant" to the OP's stated "best" criteria ? A temp of 65.75 is not better than 51.75
2. The OP's stated budget is £100 ..... so, to my mind anyway, recommending any $30 (£18) coolers....well just wouldn't be .... er .... "relevant" to the OPs inquiry.
So, let me make an alternative suggestion ..... in the future...... try and make suggestions that are "relevant" and / or actually responsive to the original post, not replacing his desired criteria with your own, and not criticize others for giving answers which are, in point of fact, responsive to the OPs stated criteria.