I'm going to make an absolute statement here.
Go buy the Dillon 550B !!!!
There are 10 times the Dillons out there as Hornadays. There is a reason for this(actually several) and it ain't the pretty blue color.
It is just a far better product. Also Dillon makes upgrades to their machines that retrofit to existing machines.
Hornaday drops machines and stops producing replacement parts shortly there after. Ask me about my DL266 loaders and where the replacement parts come from.
I HAVE TO MAKE THEM! Just finished a .410 Drop tube an hour ago for my .410 DL266 cuz Hornaday nolonger has any parts for them!
If you read the posts above you'll notice most of them are positive for Dillons.
As far as speed of change over I can go from .308 to .45ACP in about 1 minute. .223 to .308 since I have to change from small to large primers is 5 minutes.
Also thier customer service is excellent, it's very hard for me to believe horror stories about them simply because in 25 years I have never had anything but positive experiences.
Your choice, but I'd have a good look and talk to as many people as possible, although the responses from above and continuing on this thread will pretty much tell you the way it is going to go.
There's a good reason for this, and it ain't the pretty blue color!
Randy