I was faced with this decision recently, and I choose to play Walsh's parts, because, well . . . Joe is a goofy, tasty, quirky, singularly unique badazz on guitar. Who wouldn't want to play those wicked licks? Don't get me wrong, Felder is a masterful player, so controlled and elegant, but Joe has this "sounds like he's going off the rails but always recovers" facet to his playing that I find so exciting. And the phaser is heavenly on Joe's track. I've got a MXR reissue Script Phase 90 and a vintage 70s EHX Small Stone, so I'll use one of those when I perform the song.
If you are unable to answer the question because you don't know who plays which parts, then I've got to wonder what the heck you're doing on a guitar forum in the first place?!? It's one of the most iconic guitar solos of all time. Go do some studying and come back when you're ready to hang with the grown folk.

