I took the plunge 14 months ago and upgraded from my 1975 Elna Super. You are correct. It is a HUGE change. I love my new machine and still I'm trying to learn all it can do. Only started learning the embroidery a couple months ago so learning a whole new world there. Join the 8 series yahoo group. Take advantages of any and all classes your dealer or other nearby dealer is offering. Download and view the 820 and 830 Mastery classes.
http://www.itsastitchonline.com/machine_mastery.htm There are many projects on the Bernina website for 820 and 830 machines that are for teaching. Sign up for the Bernina newsletter so you will be notified about the free webinars they do fairly regularly. Old ones are posted on this website.
http://www.exnovodesign.com/ . Bernina has offered through dealers a monthly Bernina Vitual Club and Bernina Software Sampler Club. More info about these are available on their website or with your dealer. Not all is specific to the 830, but I've learned so much about the different feet and techniques. There are many, many learning opportunities and to learn this machine it is important to take advantage of them. Good luck and enjoy!