At least you aren't like me and bought the AS GRP puck which is listed as compatible for a 728. However, it will only work with that unit when they release software version 6.3 and it's currently only 6.250 and they have no answer on when they will update it for the the 728. They are selling something as being compatible when it really isn't at this time. The older ASGR50 puck worked fine but is no longer sold.