new fishfinder xducer question?

[SECF3114M73J]

I have a Lowrance unit, I also mounted my xducer in the bilge just off the center line. The techs at a marine electronics store suggested not shooting through the keel. It's mounted on the deadrise but with the boat rocking you rarely get a straight up and down shot anyhow. I also bedded the face in a splooge of Boat lIfe. It works great, holds bottom at all speeds.