You are fortunate enough to get free tickets (something a lot of people would dearly love to have). It's a company that is new to you. It may be a country whose theater you are unfamiliar with. The critics have been generally positive. Even Jesse Green addressed some of your concerns that the shows are "enthusiastic....well-meaning....[and] nice" but he still seemed to come down in favor of them. Why not go?
I don't know if you are old and infirm and getting on the M42 is a big challenge for you; or if you are a very important person who should be off saving lives or fighting fires. If that's you, then maybe don't go.
But I really don't see that 90 minutes is going to be that much of a dent in your life.