If he is not good as English, when troubles poped 
up, how can we solve the problem? 
It is possible of bad communication in this case! 
I don't think most of us know Japanese and can 
communicate with him in Japanese. 
I think the best deputy service should be good at 
many languages(you don't know where your 
customers come from!) and a "pro" on fast 
transaction & cares on the stuffs!!

By the way, you said you  didn't try them before, 
then, why you know they are a "HE" ?!