The BETA is $50, not $45.
It will contain: The small Gene scene, the small Janet scene, and the beginning portion of the large Terrance scene.
The whole point of a BETA is to give people a small taste of the upcoming full release. You don't have to buy it. It is for those who don't want to wait longer, and to help support the game even further financially buy buying something very exclusive that most people won't get. It also helps us recuperate the money lost when the full release has leaks.