Moissanite rings look great, but I'd leave them for engagement only - as they look so close to engagement rings. If you're worried about color, I wouldn't fret. Most people think they look clearer than most. Some people that can tell a difference say you just need to get the 'enhanced' moissanite and then it looks just as clear, if not more. There's a side by side comparison here: http://www.moissanitevsdiamondrings.com/differences-between-moissanite-and-diamond/
I think moissanite rings are simply an affordable and anyways a better idea to enjoy the brilliance and sparkle that diamonds show. Although, moissanite is completely a different stone from diamond, many of its characteristics matches with diamonds. As moissanite is lab created, doesn't speak about any history, it is anyways affordable.