I personally have and my suggestion is don't unless you don't expect A+ quality and are prepared for possible problems. A couple months ago, I purchased this exact "Flytouch 3." The resistive screen was not so responsive, while it did work great as a mobile media player sometimes, image quality was okay at best. Sound....really bad coming out of this device and weak, which is a common complaint. There seems to be several models of these floating around, but you won't know until you've gotten yours and checked system info in the OS, which is Disco or disco10, Sawee or Sawee10 or Generic.
I had the generic model which seemed to be okay when rooting and installing some of the firmwares floating around. BUT the disco or disco10 model has had more people running in to system crash or locking when trying to root the device.
Anyway, after owning it for a week...I had to send it back. The price for what it is and the unresponsiveness of the screen and poor image quality was not justified. While the price makes it tempting........when you get it in your hands, you quickly realize the device should have been $50-$75 bucks.......and that may still be too generous.
I suggest you do a little more research on it. You'll find that there are more complaints and negatives than there are praises and positives.
Here's where I had got mine.