I just ordered the new Yongnuo wireless TTL triggers YN-622 for Canon. They appeared lately on the market and I want to compare them against the Pixel Kings. The most obvious difference is the support of flash ratios, the transceiver design and the supported TTL-flash on the transmitter. There is no way to update the firmware once it left the factory but I'll see if this is really an issue. So far the firmware improvements of the Pixel King did not help me to fix any issue. I guess I'll have to wait one or two weeks from now. I'll let you know about the unboxing and I'll create a review later on.
YN-622 Wireless TTL Trigger