I am a wrapper, but Beco. Beco is the only SSC I have tried that doesn't dig into my body quickly. Ergos just don't hit me right. It really comes down to how it fits your unique body.
More Green For Less Green
Ergo is on sale at Target right now. I like mine.
if you're in the market for one, I would try them out first, everyone is different.
I LOVE my Ergo carrier, I had no back pain (even though I had old ladies telling me I'm ruining my spine by carrying my child, seriously they said that) All the weight was balanced on my hips, I guess one down side would be your baby can't face forward like the babybyorn, but you can have your child sit "side saddle". Along with piggy back.
But definitely go to places such as Babies R Us or Buy Buy Baby and ask to try out the carriers to find which one works best with you.