"When buying a PC it's never been clear to consumers exactly what an AMD processor is or what its equivalence to Intel processors is"
Same problem here ... There was a time when I would always buy AMD over Intel but over the years it's become difficult to know at first glance what an AMD chip does now. Seems to be no coherent way for the layman to tell one chips performance over another at a glance.
Intel
i3 - good
i5 - better
i7 - best
AMD
Athlon - ?
FX4 - ?
FX6 - ?
FX8 - ?
A8 - ?
A10 - ?
FX<insert random number here> - ?