What I like about The Green Lantern Corps is that they accept you in based upon your inner strength and fearlessness, not on what race, planet or creed. A fearless Saiyan is as good as a fearless Erudite in the eyes of The Guardians of Oa.
Of course if and when the Power Ring runs out of power, the Saiyan can still kick butt while the Erudite would be forced to use magic or pee in his robe, whichever is funnier. Heh.
Don't mind me, my humor is as twisted as a Twizzler.