If you look at it, ombre actually looks WAY better on curls, because it looks alot more blended and a more natural transition. I DIY-ed ombre on my 3b hair, and I had it for about 4 months and loved it(:

why I'm struggling to find pictures, I don't know..but I did love it, I say go for it! and do it at home to save lots of money, it's VERY easy..I used the kit, L'oreal Wild Ombre