The Beco is similar to the Ergo, it's more a matter of which one fits better. There are many other similar kinds of carriers (soft structured carriers), but they all have slightly different features, body size/shape, straps and waistband designs, etc. I found the Ergo to be too thick/padded for my liking, especially for summer wearing.
Without knowing your DS and what he does when he's in the carrier, it's hard to know whether he'll have a different opinion about other carriers.. how is he "uncomfy" when he's in the Ergo, is it something about the fit or does he get too hot?
When are you making the trip? Is there a babywearing group (or even just another BWing mama) nearby that might allow you to try on some carriers before you go?
(LOL.. and off-topic, but I like D?, -6 months in your sig

)