However, if you remind me of your flight instruction qualifications and how
many students you have successfully transitioned from a Warrier to a C172SP

I've successfully transitioned students into aircraft ranging from
gliders and old-fashioned ragwings to complex singles like the Mooney
and Bonanza, and even the odd twin. From where I'm sitting, he's right
and you're wrong. An hour is plenty of time to deal with issues like
fuel injection vs carb heat. It's nowhere near enough to get full
utility from a glass panel, but it's more than enough time to get the
same utility a pilot would get from a conventional panel. Someone who
is current and proficient in a Warrior should not need more than an
hour max to transition into a Skyhawk regardless of engine and
avionics.

Also, I think it's ridiculous to require recency of experience in make
and model - recency of experience makes sense for a class of airplane,
and a Warrior and Skyhawk are the same class.

Michael