Recently I studied the use of ~みたい to indicate something one wanted to do, but ~みたい is followed by です。 Now my understanding is that adding です makes the sentence polite, so in informal conversation it can be dropped. Is this also true of ~てみたい as featured in Beginner Lesson #165, "House of Horrors"? Can I or should I add です to make it formal, or is this not necessary for this construction?
Thanks!
Jason