ESCs: The ESCs that come with the above sets are fine. I am currently using the Q Brain 4 in one ESC, which mounts in the center of the quad. This makes a neater installation, but I had to add another "deck" to make a place for it.
Q Brain 4 x 20A Brushless Quadcopter ESC 2-4S 3A SBEC
Also good are the Hobby King Afro series that are designed for multicopters. They are "flashed" with "Simon K" software that is more responsive for the quick changes that multirotors require.
Afro Slim 20Amp Multi-rotor Motor Speed Controller (SimonK Firmware)
PROPS: I would order a good supply of Gemfan 8x4.5 props (orange and green for orientation, clockwise and counter clockwise). They will break and you don't want to be grounded for lack of a $1 prop. Order from Goodluckbuy.com if you are ordering the X525 combo. If not you can order from Hobby King USA.
Hobby King USA
8045 SF Props 2pc CW 2 pc CCW Rotation (Orange)
8045 SF Props 2pc CW 2 pc CCW Rotation (Blue)
8045 SF Props 2pc CW 2 pc CCW Rotation (Red)
FLIGHT CONTROL: NAZA M LITE flight control system. This is a commercial grade software at a hobby price. You can order this with or without GPS. GPS ads accurate Position Hold, Return-To-Home and Intelligent Orientation Control functionalities. GPS is worth the money.
Dji Naza-M Lite Multi-rotor Flight Control System with GPS Compass BEC LED Module
DJI Naza-M Lite Multirotor Gyro System w/ GPS
LEDs: LED strips for the bottom of the arms, necessary for orientation, in my opinion.
Turnigy High Density R/C LED Flexible Strip-White (1mtr)
Orvac Electronics, 1200 S Shamrock, Monrovia CA
Turnigy High Density R/C LED Flexible Strip-Red (1mtr)
Hobbyking X525 V3 Glass Fiber Motor Mount (4pcs/bag)
Aluminum Square Tube DIY Multi-Rotor 12.8x12.8x250mm X525 (.5Inch) (Red)
Aluminum Square Tube DIY Multi-Rotor 12.8x12.8x250mm X525 (.5Inch) (Black)
RADIO: The more channels the better up to 7. End point adjustment and a 3-position channel switch is helpful. A 2.4 radio with a small receiver is best.
BATTERY: 3s lipo, 2200maH or higher. 20C seems sufficient.
READ: Visit RCGroups multicopter forums and read everything you can.
My History with Quads
Searching eBay and the internet, he coolest looking quad at the time was the IFly-4 by Ideafly. These are still available with more modern controls, from Hobby King.For $219 still not a bad deal. I bought one on eBay with some extra parts and a "Rabbit" control board. I had to dig to see how the board worked. It had an intimidating
row of LEDS at the front, that flashed in mysterious patterns and colors, that seemed do convey some meaning. Remeber the lights on the space ship from Close Encounters? I was able to find some badly translated documentation. I learned early that best source of information for all things quad is RCGroups.com.
Flight Control Board Background
This is probably a good point to talk about flight control boards (referred to as FC). They are the heart and brain of the quad, and what makes multirotor flight possible. Most of us are at the point that we have some understanding of LiPo batteries, brushless motors and ESCs, volts, watts and amps. Those are the airframe of MCs. (See what I mean about learning new things - how many of us knew about these things five years ago?). Anyway the control boards (FC) are a fortuitous convergence of technologies.
The computing power of the FC is provided by various micro-computer chips. Imbedded computers are in everything from wristwatchs to stoves and our cars. Everywhere. Many are made by a company called Atemel and they make lots of different kinds.The thing they have in common is that 1) they are programmable, 2) they take electrical inputs and 3) process the inputs to create useful outputs. Some clever Italians installed one of these on a small circuit board with easily accessable inputs and outputs, and developed a computer interface that made it possible, and relatively, easy for hobbyists and artists to program. Usefulness is only limited by the imagination.
This system is called Arduino (Italian for something like "little worker"). Go to http://www.arduino.cc/ to learn more about that fascinating world.
Other hobbyists found various sensors to provide real world input. To fly a multicopter, certain movements must be sensed. What commercial technology could the hobbyists tap into. Wii game controllers! The "nunchuks" contained tiny accelerometers and gyros! And they were cheap! So, hobbyists took these out of the nunchuk and installed them on a board with outputs that could be linked to the Arduino. The Arduino now could sense movement.
Flight Control Programs
Now that the Arduino had the input sensors for movement, these inputs had to be processed into output that could fly an MR. Again the hobby and Open Source programming community to the rescue. Smart progrmmers with time on their hands adapted control theory programming to provide the necessary corrections to the motors. Movement sensed in an undesired direction or rate was counteracted by speeding up or slowing one or more of the motors. The theory used is commonly known as the P.I.D. system. Changes are sensed, and control reactions in the form of speeding or slowing motors are output, while compensating for over or under-reacting. The resulting Arduino program was named MultiWii based on the use of the Wii controller sensors. This is an open source program, meaning the no one owns it, anyone can modify it and distribute it (not for profit). Background, help and the latest version may be found at the MultiWii.com wiki. Other similar programs are BradWii, and APMP. Each have their own features and fans. Some commercial controllers such as DJI NAZA , Hoverfly, and APM use their own proprietary programming.
The Quest Continues