I haven't compared both but they aren't the same type of device. The I20 is a digital dock which offers a built-in dac for emergencies only. It extracts the digital data from the ipod in the same way as the Onkyo NS-D1 or wadia transports and is really designed to be used with the optical or coax digital output connected to an outboard dac . The arcam is a conventional dock with no digital output. It uses the dac that's built in to your ipod, which is not of the best quality, and tries to make the best of it with high grade components. If you're using the I20 with its own dac then you'd be better off spending any spare cash on a new dac. If you want the arcam sound then try the arcam rdac. It's had great reviews.