I have a 3 unit x60 mesh which works perfectly. I now plan to add located away from the current x60s which has ethernet only, no wifi. So I guess I need either an access point or another mesh unit. What are my best options? From an aesthetic and financial point of view, a cheaper member of the X family (X10 or 20) would be ideal - is this going to be compatible?

Daft question - there isn't a 3-unit limit? I ask because I see single, 2-pack and 3-pack versions for sale but never more.

Thanks.