Thru hull transducer?
 

How many use them... are they dependable... if glued correctly? My old plastic transducer cracked to crap... I'm thinking of thru-hull transducer.
I have a 1960 BB... it looks single hull at the bottom near the drain plug and V at the bottom. Anyone installed one before? On a BB?

clarifying
 

I mean "Shoot through the hull" no drilling holes.

They work fine as long as they are installed properly.
When you epoxy it down you can not have any air bubbles or air pockets between the transducer and the hull.

They work good. The farther forward the better.
If you can, install it under the center console.
If you put it farther to the stern, air bubbles and
engine noise can mess with it.

Engine noise? Do stern mounting transducers have the same problem?

Yes. Bubbles and sometimes engine noise when running fast can cause it to give goofy readings.
I have had that happen with Hummingbird and Lowrance depth finders mounted on the transom.
Don't happen much at slow speeds.