Transformers questions by newbies, and not-so-newbies

[Ode to a Grasshopper]

...that doesn't really answer my question.

I'm only interested in this toy if it's compatible with the original G1 Optimus Prime trailer, otherwise I really do NOT need another movie Optimus Prime toy

Can't give you a definite answer, BUT the deluxe DotM Optimus and G1 reissue Optimus they've released over here can both pull the DotM trailer, so it's fairly safe to assume they could both use the G1 trailer too.

On a later look-see, it seems that they drilled the G1 Optimus' tralier peg, so most original-mold G1 Optimii won't be able to use the DotM trailer but the DotM Deluxe from the 2-pack should be able to use the G1 trailer.

Again, it's not definite but if it uses the same mold as the Chronicles one it should work. Galleries here, sorry if this doesn't answer your question.