I haven't tried the Meguiars leather treatment as I still have some Zaino product to use up but I'm sure it is good.
For all the plastic trim plus all the weatherstripping around the doors, etc I am a big fan of 303 Aerospace protectant and have used it for years on several cars.
I buy those cheap cellulose kitchen sponges (without the scrubbing pad !) and cut them in half to use as applicators. They also work good for applying tire dressing.
Apply the 303, let it soak in for a few minutes and buff the excess with a MF towel for a nice satin finish.
I don't really see the need for a store bought cleaning product unless you have kids or a dog that really trash the interior. Usually just some mild dishwashing detergent and a damp MF towel will clean the interior prior to applying leather dressing or 303 Aerospace.