Theta David II vs Theta Carmen II

Hi,

I am currently using a Theta Carmen II. A local seller has a Theta David II for sale. If I buy the David II, will my system be better in 2 chanels audio AND hometheater video reproduction, stay the same or get worse?

I look and look at the Theta website but could not figure out which one is the older model.

Thank you for your help,

Paven