I've been looking at transducer mounting locations and looked at many pictures and I have a general question why so many people mount the transducer in an area that suffers from cavitation while on plane? Are there specific concerns I should be aware of when mounting on a lower location to get reading while on plane? Any input is appreciated.

It is very simple. The transducer has to have water contact to provide depth.

Those that have sonar units that have the imaging technology do attach those above the hull bottom, but use another transducer for depth.

If you state what sonar unit is involved and on what boat, you will get suggestions on the proper setup for it.

"One size does not fit all"

A transom mount is not recommended for speeds over 65 miles an hour, even at 50 mph it can kick up a pretty good rooster tail if it's located directly behind the pad.
Also being the lowest point of the boat you stand a chance of breaking it if you hang it up on something.
Mine is behind the pad mounted next to one of the drains.

Thank you for the input.

I have a Skeeter SL-190 and I'm looking at mounting my Garmin 93SV transducer on the transom. The boat has a dash mounted Lowrance depth gauge with a shoot thru hull transducer that seems to work fine for depth readings at any speed.

The boat does have a stepped transom and I understand that if I don't mount the transducer at the bottom of the high speed water flow line I won't be able to achieve readings at speed. My question is do I really care that I won't get readings at speed? I understand that side and down imaging works best at slower speeds but what about basic sonar? This is my first fishing oriented boat so I don't know what the best location is and what the recommended.

Remember, everything you see on your screen is history. If you're running 60mph and see something of interest on your screen, it's going to be very far behind you by the time your fish finder processes it and your brain processes it. Going that fast, I hope you would be watching where you're going and not looking at your screen. I don't use my 2D at high speed but that's just me. I'm sure others do.

I decided to mount the transducer at the bottom of the high speed water flow line. I'm not too concerned about protecting the transducer, I'll take my chances. Just need to mount the cable and I'll update results once I test it out.