I suggest skipping retracts on the second plane.

Reason: Retracts are a PAIN in the BUTT!!!!

Your second plane is the one that you will be doing the most learning with. Sure, your trainer taught you the basics, but now you're going to learn how to really tear up the sky. Your second plane will be a vast learning experience, adding retracts will vastly increase that learning curve! I say avoid them until you are a proficient flier - even to the point where you are starting to get bored. Because retracts will take up 90% of your preflight/postflight time (at least at first until you have the hang of them, then they will only take up 50% of the time).