Yes, on both accounts. We run an iPECS 50B at our office. We are able to log on with both Ez Attendants however when we log on the second one it "cuts off, cancels, affects the operation" (for want of a better technical description) of the first one.
We have all the technical documentation supplied by our National LG Dealer, thank you. Something to note which is different with the Ez Attendant and Ipecs is that there is only one unlock code required and then you can run up to 4 Ez Attendants.
In theory, if you tenant the switch... say 3 ways then one could get to run 12 Ez Attendants. This has not been tried by our national supplier however. It seems unbelievable but we have read our sales documentation very carefully and have questioned national supplier and they do not disagree with us. (just waiting for them to confirm that it can be done).