Active EMG's have a certain 'sound' due to the low impedance winding and the internal preamp. Some consider them to be 'hifi' sounding, others consider them 'bright' and 'harsh'. HZ's do not have that signature active EMG sound. They are not internally active and cost less to make. Hence, some people consider them 'not real EMG's'. They are certainly not active EMG's, which are considered one of the top 3 or 4 big name pickups. They cost less to make, sound different, and cost less to purchase as well. A lot of mid priced instruments use them, so that they have a recognizable brand name on the pickups. Much like a lot of mid priced instruments using the Bartolini MK-1 pickup, which like EMG HZs are not considered 'real Barts'.