I am a product of the 80's so pretty much anything from that era, but my favorite band is Journey (With Steve Perry of course). To this day there has never been a voice so pure and unmatched to my ears. How they are not in the HoF is beyond me, especially given the quesionable inductee's in there now. I'm just glad i got to see him twice in his prime. Hoping someday soon he'll release the material he has in the can, and perhaps a reunion with the band (although the way things went down it seems highly unlikely).
Probably his greatest vocal performance (caught on tape anyway) was Houston in 1981. Mother Father was just flat out sick, and i'm pretty sure celestial angels appeared in the sky right around the 4:58 mark.