Fundamentally this is an answer you already know, but perhaps you don't know how to express it? I assume you picked EZ-Robot over those others, correct? What caused you to pick it over the others?

For a list of reason, you need look no further than the home page and the Why Choose EZ-Robot page:
https://synthiam.com/About/Default.aspx

Why Choose EZ-Robot:

Programming in C or Assembler on a microcontroller is tricky and complicated. However, the EZ-B is controlled from either the graphical ARC Software or Visual Studio .Net on your PC. The EZ-B is easily re-usable and does not require flashing or reprogramming per project.

The less time you spend fiddling with compilers, hardware programmers and debuggers, the more time you spend building and designing robotic projects. Do those words confuse you? Compiler? Microcontroller? If so, then the EZ-B is for you!

The EZ-B Project scales from beginner to advanced users. With the purchase of the EZ-B includes lifetime firmware upgrades, you will never again need to buy another robot controller board.

Most of all, EZ-Robot is not just a project... It is a community of like-minded enthusiasts with a passion for robotics. EZ-Robot brings people together from all over the world to make personal robotics a reality. [Visit Community Forum]

@JustinRatliff: i already read that... but what i want to know is the deepest part which i dunno and i need to know about that to impress my teacher about EZ-robot...

Deepest part, I'm not sure what you are getting at.

Perhaps DJSures Own answers in thread 1489 would address your question:

"Arduino and EZ-B are very different - much like EZ-B and Microchip PIC are different. The concept behind EZ-Robot (combining the EZ-B and software) is leveraging the processing power of your computer to compensate for the lack of processing in MicroControllers. The true power of the platform is in the EZ-SDK, but it's only used by a few advanced users and rapid prototyping education/industry organizations we deal with. CMUCam is neat, but again limiting if you're expectations are scalability. You can even connect ROS to the EZ-SDK. And within the ARC, you can create your own controls and customize the environment.

Tethering is actually an interesting word - it has a bad rep but is a very popular and scalable control method. Internationally, advanced robots contain computer's and external hardware I/O. So technically, even our customers (such as NASA and MIT) use a computer with the EZ-B as an external hardware I/O. You'll enjoy having a computer operate the robot in real-time because it provides a graphical interface to "tweak" and "customize" the robot interface. You will always be tweaking values and showing-off the graphics to your friends. Most people are interested in the Project before the robot Smile - You'll get used to the question "How did you do that?", everyone wants to see!

Having the PC also enables so many other control methods. Such as telnet consoles, wii remotes, web servers, speech recognition, etc.. the list is huge and grows weekly. Oh yeah, our Windows 8 tablet (i guess its called Surface now) support is pretty awesome too."

Easy answer...

BECAUSE IT'S BETTER

The benefits of the EZ-B V4 are on the store pages and in the datasheets within the learn section. The hardware is more advanced than that of the Pi and Arduino.

Not to mention the biggest reason of all to use an EZ-B... the community is second to none, the support you will receive should you run in to any trouble (no matter how small) is almost immediate and of extremely high quality.

Why would you want to use a Pi or Arduino which both require extensive coding and many many months of typing away on a keyboard when you could use an EZ-B V4 which requires less than 30 minutes of clicking and dragging to achieve better results?

Because at EZ-Robot, we care about the future of robotics and make it easy for you to invent robotic solutions... We make robotics possible. That's why.

Arduino? It blinks LEDs.

Raspberry Pi? It's an XBMC media center for pirated video content.

If you are looking for a more technical reason take a look at DJSures notes from Build Release 2014.3.27.00 in thread 5418

"This is an update to the EZ-B v3 firmware in preparation for shipping the v4. As you know, the v4 has amazing bandwidth and super low latency of all asynchronous events (i.e. streaming video, streaming audio, commands, etc.). The bandwidth of the EZ-B v4 is 6.66 mbps, which is a kabillion times faster than the 9600 bps of EZ-B v3. The ARC and EZ-SDK had filters which prevented too much data from flooding the communication channel of the EZ-B v3. Well, I have learned a thing or two while designing the v4.

The communication protocol between the client and EZ-B has always been very optimized and efficient - that was never a concern. However, how the EZ-B internally processes and buffers the incoming commands was improved. While designing the v4, I took advantage of the ARM CPU's many DMA channels. DMA is the Direct Memory Access feature of full featured processors; even found on in your PC. With DMA, the processor does not need to use expensive program instructions to perform simple tasks between Peripherals (hardware) and Memory. The EZ-B v4 has 8 DMA channels actively operating to buffer data between peripherals and the memory... This allow the main program to use it's impressive 120mhz processing speed effectively."

Wow Justin, I wrote that? Sounds smart! Almost like I know what i'm doing... Almost!

And you could take a look at the datasheet for the EZ-bv4 : https://synthiam.com/Tutorials/Files/EZ-Bv4%20Datasheet.pdf

"The EZ-Bv4 takes robotics to the next level, with Wi-Fi, Video, Audio capabilities, and the standard features you’ve come to love from the previous generation EZ-B. The v4 allows your robot to track objects/motion/colors/faces, speak, play music, move servos, read sensors, control H-bridges and more. Connect your Laptop/PC or Mobile device to the EZ-B v4 through an Adhoc or Client connection over Wi-Fi. Both options can be fully configured with the embedded Web Server. The v4 leverages the power and speed of two 32-bit processors (120 MHz ARM Cortex-M3 and 80MHz Microchip PIC32). It is also very expandable with 3 x I2C headers for additional sensors and displays, 24 multi-use Digital I/O, 8 x Analog-to-Digital and Dynamixel servo support. Let the Robot Revolution begin!"

Arduino and Pi can't compete with those features or specifications when it comes to robotics application.