I have both.... actually a few of each of them..lol.. and really enjoy them!!!
For a brief comparison between the Blade Chroma and Yuneec Q500.... The Q500 seems more Stable in windy conditions as it doesn't seem to move around as much like the Chroma. Both have similar flight times, both have very good camera quality with the CGO3. I guess the downside to the Q500 is its SIZE though, especially with the Props mounted on it. I have my Chroma in the Hard Case with the Props left on it for quick access so i don't have to keep putting them on like i do with the Q500. The Q500 i have in a backpack and have to attach the props each time.
Also.. just remembered.. The Blade Chroma is a lot easier to repair if you crash it, Its basically plug and play. The Q500, you will have to know how to do some soldering in order to replace the body. The Q500 body is fragile to say the least. Parts are still available for both models... but like Wingshooter said, the Chroma is no longer being made. (That's why I have a few of them stashed in the garage for future use.....lol)
Like i said.. I enjoy flying both... but I like the Chroma with the Spektrum Receiver in it so I can use my DX6 or DX9 to fly in different modes, and not just to take video or pics. The Q500 is limited to the ST10+ transmitter. I do have to say, the Chroma can really move.. and with the modified setup for the 350QX3, I get all the Flight modes including STAGILTY MODE .. which is a blast. I usually get a good 13- 15 mins of hard flying in with this setup before the battery gets around 11.4v.
I recently wired in a Chroma Reciever in a Q500 and I am slowly working out the settings on it to fly with the DX6 as well. Should be interesting. So far so good though.