Don't Install If You Hate Dealing With Problems
If you don't want to deal with bugs and other problems you probably shouldn't download the Galaxy Note 9's Android Pie beta.
There's a reason Samsung calls this a beta. Samsung's software is unfinished and unfinished software can cause major problems.
Beta testers are already reporting issues including problems with apps, abnormal battery drain, Bluetooth issues, Wi-Fi issues, UI lag, installation problems, and an assortment of other bugs.
Samsung's rolled out new betas to correct some of these issues, but problems will plague the software throughout the testing process.
If you depend on your Galaxy Note 9 to get you through the day and don't have time to deal with major problems, you'll probably want to avoid the beta.