I have had an Ergo for about a year, it fits me well and I use it everyday.
Back about 2 months ago I won a Boba 3G at the Great Cloth Diaper Change. Maybe it's my bias or the fact I'm 6'1" and 240lbs but it just didn't seem to fit as well. The rise seemed to be shorter so less of my sons back had support. I should point out DS is 11 months and 26lbs.
I think on a smaller frame the Boba would be great and it has so many extra features that are wonderful. Anyways, I kept the Ergo and sold the Boba but really did like the product.
I had a Ergo Sport and Boba 3G. Honestly they are just really different and for us were good at different points. My Ergo Sport was super comfy until DD hit about a year (she's always been off the charts for height and about 70% for weight though so keep that in mind) and then the back started to feel too low and when she would arch back it wasnt comfortable at all. We put it away for our next kiddo and got our Boba.
I will agree with the previous poster that I didnt think the shoulders were comfortable on a taller momma (I'm 6'1 as well, about 180 lbs and broad shouldered) and as DD got to about 20 months (32 lbs) it got REALLY uncomfortable to the point I had to resell it because it felt like it was pulling my shoulders into a wierd position. I didnt have the problem the other poster had with the back being too low, that was the one thing that I really liked about it how high the back was.
Honestly having now tried several other lesser known carriers (Kanga, Olives&Applesauce and DreamCarrier) I would really recommend either a Kanga or a DreamCarrier with Neo straps to a new momma. You can get either of them used on FSOT on thebabywearer.com pretty easily for probably 100-120 bucks and they are by far the most comfy SSCs I have used. If you want something more easily accessible then I would go with and Ergo Performance or Ergo Sport for the lighter weight fabric than the standard Ergo.