If you use an extension ladder make sure you run it 3' above the roof. Put something on the edge of the roof where the ladder makes contact or you'll scratch the paint off the trim. IMO the TT's ladder is way safer. It's solid and won't slide. An extension ladder call slide sideways easily.
On our last TT we had no ladder. I used an extension ladder. I had to be 2x as careful getting off and on the roof. A fixed ladder is safer.
OSHA requires that extension ladders to be tied off at the top for a reason. If you lean to one side it will flip on you. Heard of too many accidents while in construction to be leery of them.
My advice is that if you use an extension ladder is to have someone hold the bottom while you climb it.