None which will be helpful. MP3's quite simply do not give you the subtleties that are everything in pickup choice.
For me, the problem is less the MP3's (assuming a high fidselity rate - I usually go straight to 256kbps), but rather the complex interplay between all the OTHER factors that influence your tone.
I mean, a pickup is really important, true. But, that pickup is in 1.) a guitar made of a particular body wood which may not be the same as yours, 2.) strung up with potentially a different brand and gauge of strings than you use, 3.) potentially running through a number of different FX processors, 4.) plugged into an amp that is most likely not the same as yours, 5.) dialed in with that player's, and not your, amp settings, 6.) recorded in a different acoustical environment than you are used to hearing your rig, 7.) mic'd up, which means that the player's recording abilities and "taste" in micing strategy come into play, to say nothing of the fact an amp mic'd sounds very different from one in the room, 8.) colored by that mic, which may or may not be the same as what you like to use, 9.) running though potentially a number of outboard pre's and EQ's before it hits tape, 10.) potentially subjected to amount of post-processing (EQ's, compressions, delays/verbs, etc), and 11.) considered "a good indication of the sound of these pickups) through that player's monitors in his room on playback, which may or may not translate well to yours.
Anyway, what do you mean by "rock?" the Rolling Stones? Link Wray? The Smashing Pumpkins? Guns N Roses? Howlin' Wolf?
Light, I'm definitely curious to check those pickups out, dude.
