I don't regularly watch either of the two but nigahiga is definitely funnier than raywj. Ray's alright and some of his videos are entertaining but I hardly laugh at his videos, not even when I'm high. Nigahiga's older videos aren't too great but his newer ones (2010-present) are definitly more entertaining than raywj imo.
Thunderf00t and LiberalViewer are the best though. And Catie because her Boxxy videos are awesome, especially the first three. :]