I started loading on a 650 with a case feeder just a couple of months ago and with great success. At the time I didn't know anyone who used this press so I got the Dillion installation video. I took it very slow at first by only running one piece of brass through all 5 stations, carefully observing the operation of the press. I did this to make sure that I understood what happened at every step of the operation, and how the press worked at each of the stations. It's critical that you understand what happens at each of the 5 stations.
It wasn't very long before I was comfortable with the 650 and I was loading better than factory ammunition progressively.
Here are a few suggestions/tips:
Purchase the installation DVD
Purchase the spare parts kit - a must
Make sure that your press is level and clean
Do not overtighen anything - snug is sufficient
Get the strong mount - highly recommended
Get the optional roller handle - highly recommended
Avoid all distractions (music, TV, pets, etc.) when loading
Make sure that your press is stable - the strong mounts will also help
Make sure you get the station 3 powder check system - a must for safety
If your budget allows get a second primer punch assembly - primer conversions are a snap
When leaving the press for any reason ALWAYS leave the press handle in the down position so when you get back, you will ALWAYS properly seat the primer during the next cycle
Just take your time and you'll be fine.
Safe and happy reloading !!!