Hi Leon

Just worked on a Hyster r1.4 matrix early this week.
it had 2 AC Zapi controllers. The one good thing was my standard zapi handset allowed me to access the units and make parameter changes.
Also if i had to guess controllers from zapi would be possibly cheaper than from BT, and Zapi near us are very good when it comes to their controller repairs.

Whereas BT stuff i have had difficulty repairing them myself or getting them repaired anywhere, and price wise has always been very expensive.

They do have Zappi controllers. As to if they are comparable with BT; it will probably be all down to the application.