It's great that you are taking an initiative in building/replicating one like EZ-Robot. I I would like to add a few things which helps in building a robot.:
Simplicity.
Cost Factor.
With SimplicityBy simplicity I mean, choosing the right most hardware that actually helps your prototype to be built faster and the testing/debugging is easier. For instance, if you choose: Raspberry Pi Raspberry Pi with wifia Wi-Fi module (I saw one at adafruitAdafruit stores for around \$12), the whole setup may be build under \$50US$12), the whole setup may be build under US$50. Adding Computer Visioncomputer vision (I think this will boost up the investment price) since it already runs Linux on it, helps in achieving the ease in usability and development. Now you have a system that can be controlled by many components. Using a bluetoothBluetooth module with RaspRaspberry Pi is much cheaper than you may think. Chinese modules are cheap, like \$5-\$10US$5-US$10. Hereby you will have an independent robot.
But as you say, you wish to remotely control, the arduinoArduino keeping your PC (Sincesince you mentioned Visual Studio), this can be done easily by adding wifia Wi-Fi module, but Xbee cost'sXbee costs are really high, and then use the httpHTTP protocol to control the robot. The arduinoArduino will be fed with some input, like say numbers ranging from 1-100 that may accumulate 100 tasks. Like move left, right, up down, turn on the light, etc.
So essentially make sure, which development board may help you serve the purpose easily.