most low end or entry level FF/DF's will work, you have to get the settings set right for your boat, etc. One thing to really make sure of is that the power supply for the FF is seperated from any other power supply wires as much as possible to cut down/reduce any outside electrical interference(engine/TM). Cross any power wires at 90 degrees if possible and you should be ok. BPS had an eagle 320 for $80 a week or 2 ago.
GO BIG ORANGE !
I meant to behave, but there were just way too many other options available at the time.