Pocketbook says go with the 797. Ego side of brain and eyes say go with the 997. Anyone used both? Is the 797 easy enough to see both the map and the SI sonar in a split screen? Im wondering as far as mounting in a P4 (2003 Pantera IV) dash goes, if the 997 will fit in the hole I currently have in the dash with a Lowrance X-15 MT in it, or if I will have to modify the dash? If I have to RAM mount it or some such thing anyway, maybe the 797 would be better? Also, where would be the best place for me to mount a SI transducer on the transom? Thanks for any info.