I purchased this item to avoid having to run an HDMI cable to my projector from my AV receiver. Ultimately I ended up returning it for two primary reasons described below related to my setup. Otherwise, I found the picture quality to be great (no noticeable difference from HDMI cable), the setup to be very easy and performance to be fairly consistent (had to reboot every now and then to reestablish the connection between transmitter and receiver/occasional hiccups in picture quality. I did not test the range enough to comment there). If you're looking at this item to send both audio and video to a TV simultaneously (i.e., non-projector or no AV receiver setup), then I would recommend it.
1) Video latency - the extent of latency varied from barely perceptible to just enough to be distracting. It was never horrible but it's the type of thing you can't ignore even more so because you know it might show up anytime. To the manufacturer's credit, the device does feature a gaming mode which reduces picture quality to cut down on latency, but that was not a tradeoff i wanted to make for my regular tv viewing. I did not experiment too much with this mode to comment on the actual extent of quality sacrificed. However, I do not expect it would have made too much of a difference for me given my setup, i.e. my issue is primarily due to audio and video traveling different paths (see setup notes below) rather than the speed of the transmission overall.
2) HDMI/CEC issues - one of my favorite features of my Chromecast is its ability to automatically turn my AV receiver on and switch inputs when I cast a video. For whatever reason, these features stopped working when the wireless transmitter, rather than my TV directly, was connected to the HDMI out port. These features also stopped working for my ps3.
All of my content sources (cable, Chromecast, laptop, etc) are plugged directly into my AV receiver via HDMI and my AV receiver is directly connected to my surround speakers. The wireless transmitter was plugged into the HDMI out of my AV receiver and the wireless receiver was plugged into my projector.
I moved my AV cabinet and am using an old fashioned HDMI cable from my AV receiver to my projector. Initially I wanted to avoid this setup as I had to split my cable line now to service internet and TV - also, I no longer have line of sight for my IR remotes. Bottom line is that you're going to have some tradeoffs in your setup no matter what. Decide what's important for you and perhaps this item could be a part of it.