Cheapest and easiest Arduino board for 12 bit ADC, thinking of M0 I need an Arduino board for simple ADC, but 10 bits of resolution is sadly not enough. I am going to buy a board with 12 bits of resolution, but really couldnt decide on the exact model. It needs to be easily accessable and wont be used for anything else other then ADC. I have my eye on MO, but cant decide if i should buy the pro or the normal one, or just another Arduino board.

I take the data through USB port and the instrument will also be powered with the same USB cable.

* My only option is to use an Arduino* 

I know i can use the Aref pin or do oversampling but i really am not intrested in those options. thanks for your input
Use a Teensy 3.x. Those have 13 bit ADCs