Re: Help with figuring out which press to buy...
The progressive press that has the reputation for reliability and service is the Dillon RL550B. The others are late to the party or are the latest in several iterations because earlier examples failed. The Dillon RL550B has been around for maybe 30 years with few changes and a few updates (which owners got for free). When the Dillon entered the reloading business they gave and are still giving a lifetime warrantee. They changed the way the industry does warrantees. Today other reloading equipment manufacturers have tho follow Dillon's lead. That goes for the design too. The current progressive presses from others now look similar to the Dillon but the other's earlier progressives did not and were failures.
Dillon service is renown for being excellent. My Dillon RL550B has been rebuilt (after heavy usage over several decades) by them twice for free. Anytime I have a problem I call them and they rush a replacement part for free, no questions asked. The LEE stuff I have purchased over the years was junk (my opinion and yours may differ). I had a Hornady shotgun progressive and Hornady discontinued it because it was so bad. They would not give me any credit towards their newer supposedly better press. Hornady left me with a bad taste in my mouth for them. Dillon, on the other hand, took back a Square Deal that I had used for over a year for full value towards the RL550B just to make me happy (I had graduated from just 9mm pistol reloading to needing to reload for rifles too). Now that's SERVICE! Today I reload over 30 different cartridges on my RL550B.
As to manual indexing, it is an advantage and NOT a disadvantage. Since you have to add the bullet and case to the press manually, using both hands gets the table advanced, the new case added, and the bullet set atop the third station case in a few flowing motions. It in no way slows you down to have to advance the table manually.
The advantage of the manual indexing is it makes using the press as a single stage or turret press much easier. All progressives occasionally have a problem and the table has to be cleared in order to solve the problem . The ability to manual advance or reverse the table makes clearing the press much easier.
The LNL Hornady has a bunch of followers but there have been a much bigger bunch of Dillon RL550B owners out there who absolutely love their RL550B's and would not exchange them for the Hornady for any reason. Arguments can be made for each press based on pricing, value, but the Dillon will never loose an argument on who has the best service and the most reliable progressive press with the longest good history.
My opinion, based on 25 years ownership of my Dillon RL550B, is: forget the others... Buy the proven one, the Dillon RL550B. You will not be sorry.