Thurston Moore & Lee Ranaldo (Sonic Youth)
I used to love Sonic Youth back in the day, but are you serious?
Great guitar playing is of course not only a matter of technical prowess but mostly about creating memorable riffs (hence Slash > Buckethead). I've never met a person who thought that Thurston had either quality. Interesting opinion though.
When it comes to the 80s, I'd say that Eddie van Halen brings the best mixture of technique and memorable riffs/solos. Slash deserves mentioning because everyone knows his sound even though he never was a great player.
Edit: I thought the title was "best" not "favourite". In that regard Thurston Moore is obviously a much more legit choice.