Really, I would just hold off on purchasing anything. If you have a laptop, then just use that for the 1st semester and see how you feel about note taking. Most professors use PPT slides for lectures and from experience, the professors style will greatly vary, which may or may not make using a tablet easy. We had several professors that used the heck out of animations, which reduced needing to take down detailed notes about some stuff or needing to have a pen/stylus to draw on the slides. On the other hand, we also had a couple use word documents, which basically made the tablet worthless to me.
This is from someone who had a tablet (Galaxy Note) and a laptop going into school. I used the tablet some, but definitely not enough to feel like I would have made a good decision to just go buy one, if I did not already have it. Basically, don't go buy a device that you may realize a few months in you either don't find convenient to use or don't feel you need to use. Also, once you get onto campus, you can talk to students above you to see what they use and how they feel about devices for note taking. This will really be more relevant, as it will be in relation to the exact teaching styles and materials you will be encountering.