LauraEllen, first of all, CONGRATULATIONS!! Becoming a nurse is a tremendous accomplishment and I salute you!
About the machine... several have mentioned going with a good used machine since you are considering using it for piecing only, and I agree... I'm still using the Bernina 830 Record my parents gave me when I graduated from college in 1975. My Bernina dealer knows I'm thinking about getting a new machine, too, and made me promise to never sell this machine. He says it has been a fantastic machine all these years... and, like others, this machine just purrs! The older machines should be considered!
Listen to the excellent advice on the QB, too... there are new features on newer machines, newer than the "old 830", that you'll want to think about...
Have fun shopping and be sure to tell us what you decide!!
Happy quilting!!