I was able work with them remotely while in China for my job; this made it so much easier than if we had been working from our respective offices! They have wonderful customer service which makes communication easy when you're not even physically there anymore (or ever!).
Nothing at all really - they are very thorough before starting any project or process/transaction related task but no complaints either :) Definitely worth checking out especially since remote workers need tools like zen cargo's services now more then anything else these days!!