The ERGO definitely has a shorter body than the Beco. Some people do find this a problem, especially if they have a child who's a "leaner." Your baby shouldn't outgrow the carrier though. I carried both my kids in mine until they were 5!
I haven't heard that ERGOs were particularly better for people with longer torsos. I find the fit of both carriers a bit mysterious and I do this for a living! I have noticed that petite and narrow-shouldered mamas often prefer the Beco, but there are some who prefer the ERGO. IMO, the fit is a very personal thing and hard to predict in advance. Although in truth, most people find both to be comfortable!
Laurel
Owner, Carry Me Away
Mama to Jack, 5 and Maddy, 3