If you can get both at the same price, go with the separates, both heli's are exactly the same except for the electronics. The one you saw with everything on one board is the latest edition of the FEDA Dragonfly, early versions used separates. They can probably make it cheaper with an all-in-one board. The heli is the same.
You may have also seen the Century Hummingbird. They are both the same heli, just the Century is from a company here in America and they only sell it with separates. The Feda one is from a company in China. They both fly the same. The Century one has an extra fin on it and it also has two more supports that go from the undercarriage to about half way back on the boom. Not needed extra weight. Here is a good place to go for tips for your Hummingbird.
http://www.helihobby.com/html/tipstricks.html
I have been able to get mine to stay in a hover for about 5 seconds with no hands then it drifts off, that's only when I get the trims exactly right. It will hover nice with proper setup.
If you buy the one with the all in one board, you can only use the transmitter that comes with it. It is a Zhen Hua PCM-4CH transmitter. All of ours come in Mode 1, I had to take mine apart and change it to Mode 2. Throttle and rudder on the left stick. Not to hard. All of the directions in the box were in Chinese to. You can go here to get directions in English if you need them
http://www.amersfoortairport.com/indexe.html
Click on helicopters in the left hand column, that will take you to a new page and you will find a download for them under Dragonfly Helicopter.
Good luck