I highly recommend a mountable GPS/FF. The larger screen is way easier on older eyes than the handhelds.

I've been a little reluctant adopting new stuff, thinking it was a gimmick when color units came out, but now I can't imagine fishing without a GPS or a color depthfinder. Shut off the OB, drop the TM and pull right on top of a brushpile 500 yards from shore without hunting for it.