New is obviously an advantage. The MG1.6 is a significant improvement over earlier QR models. Some people (I am one) actually prefer the QR approach (tweeter is part of the one membrane) over the separate different-technology ribbon. I suggest you listen to both. If the QR sounds good to you, skip the ribbon.
Which Magnepans 3.5 or 1.6?
I am looking to purchase a set of Magnepans. My budget is about $1800. Would I be better off with a new set of 1.6QRs or a used set of 3.5s? I am using a CAT SL-1 mk 2 pre, Resolution Audio Opus 21 cdp, and for now an old Bryston 4B amp. My next step will be to replace the amp.