Based on the lip butters and baby lips I own, I prefer Revlon.
Lip Butters
- Larger ranger of colors
- Super pigmented -> better color payoff
- More moisturizing (for me).
- Scent free - a BIG ADVANTAGE if you don't like products with strong fragrance on your lips
Baby Lips
- Not as many color options
- Color is sheerer in general (shades like pink punch are more opaque but I still prefer Revlon shades)
- Strong fragrance
- Not as moisturizing on my lips
- SPF 20
- Cheaper (where I live)
For me, the only advantage that baby lips has over lip butters is the price. But I don't mind paying the extra $ for lip butters because I feel like the pros are worth it.
I almost hesitate to lump the two products in the same category. Lip butters are more of a hybrid between lip balms and lipsticks, more like hydrating lipsticks. Baby lips are more like true lip balms or a (somewhat) grown up version of lipsmackers haha. Chapstick with color perhaps? I reach for lip butters when I'm going out and want a more toned down lippie or if I'm just running errands. I rarely reach for baby lips because I have other lip balms that I prefer.
HTH.