I have a Dillon 550. The difference between the 550 & 650 is 4 to 5 station and auto index on the 650. The dies you use make a difference on how you load. Dillion uses two dies for seating and crimp but RCBS seats and crimps with the same die but gives you a belling die. On a Dillion press you will bell and drop powder on station #2 without the use of any die. The belling die is a feed thru die and operates the powder dump(if a case is present) and comes in a caliber conversion kit. I don't like the auto index of the 650 If you are loading primed brass the steps are different. Normally you will insert a fired case then, cycle the press, and then index the plate by hand. If you are loading primed brass you will cycle the press, insert the fired brass, and then index the plate. There will never be a brass in station #1(size and prime) when you cycle the press! Dillion uses a block to hold the dies so you never need to change the die setting. Caliber change on a Dillion takes about 5 minutes. I never used a Lee press so I can not compare but I have friends that changed from the Lee to Dillion after they started shooting competition and the round count went up!

Some reloaders install a powder dispenser on each block but that gets expensive. I have two, one w/large bar and one w/small bar! I experiment with different powders and weights so the powder dispenser gets changed almost every time I reload!
jcelect