People reload differently. Some need a caliber change rarely, some never, and some change every session or even multiple times in one session. What progressive you pick depends on what you think you need.
You have to look at all parts of a caliber change. (I'm assuming that's what you meant by die change)
Both of Dillon's popular presses have removable heads to make it so you can set up your dies before hand. The RCBS Pro 2000 also has a removable head.
Hornady and Lee offerings have stationary heads, but the Hornady has quick change collets for each die that makes changing dies faster.
Which type is better is a personal issue. Some like Hornady's method, some like the Dillon/RCBS removable head method. I personally like removable heads, which is why I narrowed my search between the Dillon 650 and the RCBS Pro 2000.
That said, you also have to change powder measure setup and often primer size. AND if you get a case feeder and/ bullet feeder, those have to be changed for different calibers as well.
Typically, the more complicated the setup is, the longer it takes to change calibers.
The fastest and simplist caliber change I've found, is on the very simple RCBS Pro 2000 with its Uniflow powder measure...without bullet or case feeders. Changing primer size takes less than 10 seconds.
Next is a Hornady, without case or bullet feeder. Though primers are not as fast to change, their powder measure is nearly identical to RCBS's, and with one $25 "quick-change kit", the P.M has an even faster caliber change. Hornady's bullet feeder changes calibers very fast (negligible in fact), contrary to the slow-to-change case feeder.
Next is Dillon's 550 and slower still because it is more complicated is Dillon's 650, encumbered by their casefeeder caliber change, primer size change, and powder measure change, many users usually prefer to load a lot (1000's) of one caliber, before they do a caliber change.
There are ways to speed up a Dillon, but that takes more money with caliber change kits and multiple powder measures. Nothing I've seen speeds up case feeder and primer changes.....maybe experienced Dillon users can offer something more there.
For the way I load, I picked the Pro 2000. If I was a successful IPSC pistol competitor shooting one caliber, I probably would have picked a Dillon 650 with a case feeder and an RCBS lockout die. If you leave it alone, I don't think there's anything faster except maybe a commercial Dillon 1050.
But for how I reload, changing calibers by session or even twice a session, among 7 pistol/rifle calibers, the Dillon didn't fit me well. With my Pro 2000, I use Hornady's bullet feeder, modified to be able to see bullet supply in the tube, and my own home grown case feeder. Both feeders are extremely fast to change calibers on compared to others. The highlight of changing calibers on my RCBS Pro 2000 is using preloaded CCI APS primer strips. Changing calibers means getting a box of preloaded strips off the shelf for the new caliber ready for to load. No tubes to load.
If I had to choose the cheaper Lees, I'd buy a press for each caliber....they are cheap enough to do that.....but the footprint is beyond my available space. Do expect to tinker with Lee's most sessions. That statement is based on my experience helping a friend keep his Pro 1000 playing nicely with just one caliber (.45ACP). I hear the Loadmasters are not any different except that they have 5 stations.
The Dillon 550B has only four stations the Lee Pro 1000 only 3. Fewer stations mean fewer options.
