A valid question.
The simple answer is (based only on my personal observation), that on average, the children of shluchim turn out better than children who grew up in frum communities.
Why is this the case? I can only assume that when a child grows up seeing his parents dedicate their entire life (literally) to Yidishkeit, that is more effective for the childs Chinuch than anything he can gain from growing up in a frum community.
(This does not mean that such a lifestyle does not come with it’s unique challenges. But the ultimate outcome has a higher success rate)