Thx for all the input so far guys. Just keep em coming. We are already gathering competence in this thread. Generally said yes it is very hard to do but after you established infrastructre opportunitys arise and you have to look at these relationships from a longterm point of view.

@gopnik:
Of course bad things can happen but you can also get into a car accident. Just because it can happen dont mean it will. Regarding the 50k usd sending limit
I think it is not a good idea to break it. Much better idea for a korean is getting all his friends involved and stay in the legal boundaries.
This is a business for people trying to grow. If you already have a certain wealth it makes not much sense. But as long as you keep transactions in certain limits there is nothing to loose. Most people work for 3-4 k eur a month. If you could have like 10 dudes where you just make 100 eur profit a week we are already talking about a second salary here. You are definetly right that under current market circumstances it is not very profitable but the premiums will hopefully rise again. Buit yes the more I reserach it the more I come to the point that it might be to less reward for such high risk strategy.
As long as the premium was 30% it looked promissing. Still not giving up on the idea. Thx for you input anyway.