I want to purchase a Bluetooth module that can program the Arduino Mega 2560. I would like for the module to able to be used with the two shields that I purchased, links to the shields are listed below. I know that I can use a Xbee product, but there are so many to choose from I am unsure of which I should get. Also I don't know if a Bluetooth device or Xbee would be more efficient.
The price range that I am willing to spend is up to 50 dollars, but depending on the device I may be willing to spend more.
Xbee Shield
Sensor Shield