Comments about Canon Canon WFT-E4A Wireless File Transmitter for the EOS-5D Mark II Digital SLR Camera:

Setting up the WFT-E4A on my own was a little tricky, but Canon technical support came to the rescue. They were very helpful. The transfer system that worked best for me was PTP. After playing with the software for a while I got some good results. The very brief documentation was not very helpful. There is one problem that I believe Canon needs to address. If you leave your camera on with the transmitter attached your battery gets drained in a few hours even when not in use. This happened more than once. Although the transmitter has an it's own battery the camera battery will drain the fastest.

Overall I like the WFT-E4A over the WFT-E1 which gave inconsistant results and required an FTP. However, Canon should address the battery problem and improve the documentation.