cryptoshift is the one that i know of. its reliable.
It has not been so long for these crypto currencies to make a strong impact in the international market and that it is just like a beginning phase for them. It will take some more time for things to get little better and that the way some of the well-recognized online shopping store like that of eBay are showing their interest in these crypto currencies is an indication that soon there will be more places which will start accepting these crypto currencies.
There are more and more major services and corporations in the world that research and accept Bitcoin as well as cryptocurrency in transactions. That shows a new trend of payment and trade in the world and I think that if you do not catch up on this trend, it will be very difficult to succeed.