Daniel Lemire specialises in high-performance algorithm implementation. In recent years he has been impressed by specific performance characteristics of Apple's CPUs. For example, their ability to eek out the maximum possible throughput from a given instruction stream's data dependencies. My information may be stale, but when I read Daniel's comments I assume that Apple is being used for compariosn because it is the current leader, and take it as given that AMD and Intel are behind. You can probably find sources where he makes head-to-head comparisons with AMD and Intel. If you're not familiar with his work I can recommend it. The Wookash podcast interview is a gentle introduction, there is open source code and academic papers if that's more your thing.