where's the "not necessary" option?
+1...
If your boat can be towed with motor full down you don't need one. If not, then you play the gambling game. Do you rely on the tilt lock to keep the motor up (which is not what it is designed for) or do you use one to prevent stern flexing. Your choice at this point. Some swear they are necessary, some don't. Do hydrofoils work? Some say they do some say they don't. Transom savers, like anything else, when misused can cause damage as well.
http://forums.iboats.com/showthread.php?t=405460
I have never had a motorized tilt before and it was recommended that I use the lock to save the tilt plungers from damage.
SO I should use the lock and retract the plungers and use a transom saver to stabilize the motor to the trailer.
I like that, Transom savers are cheap
Ahhh --
Ever follow a tinny with the outboard held in place with the tilt lock. Those devices are one-way in that they stop only downward travel. They do not restrict upward travel. Follow such a rig on a rough road and the motor is not only flopping up and down like a rag doll, but it is also flopping side to side if it happens to be a tiller steer. A tilt lock is simply not designed to take that beating.