ok, I thought I'd throw this down for my opinion. Y'all are welcome to criticize. I'm probably going to "grow" this over time...
(A) Costs are always relative. The costs listed here are the kind of prices you can expect just for the press. I left out the costs for things like shell plates, dies, etc, which can vary wildly. A caliber change for a one type of progressive press can run you over 2x more than another. Once you decide what TYPE of press, you have a lot of additional homework to do. I'm also not including all the costs for standard reloading tools like scales or calipers
(B) Load accuracy is a function of several things, but during reloading, precise and identically cocistent powder charges are critical, expecially for long range hunting loads. Turret and Progressive presses don't NORMALLY support the precise feeding of charges, although a skilled reloader will tell you that it's easy to remove the automatic powder drops from high end presses and have the same level of accuracy. While this is very true, it eliminates the key speed benefits of turret or progressive presses. Mechanical imperfections in progressive press stage rotations can also introduce microscopic changes in bullet seating and alignment, although this is more likely (again) due to the convenience of speed afforded by these presses, rather than to an inherent superiority of single-stage style presses.
(C) Turret presses come in two flavors, auto-indexing, like the Lee Turret Presses or non auto-indexing, like the Redding Turret Press. The need to manually index the press head can have a significant impact on speed. Your mileage, as they say, may vary.
(D) There's some arguments about whether a progressive press requires more workspace than a turret or single-stage press. They all need to be mounted to a sturdy location, more or less permanently, as the arm motions can cause the work surface to shift. Progressive presses, however, tend to be sturdier and impart more motion just by virtue of the constant pulling and rotation of the press. A more-fair argument, however, is that progressives require fewer motions to load the same number of cartridges
(E) This one is likely to start World War IV, but let's step back a minute. Most seasoned reloaders tend to view the world from their current experience rather than their starting experience. It's natural. I don't remember how much I struggled with Algebra when I was first learning it, but I'm pretty sure all those letters and number mixed together were pretty confusing at first. Same goes with reloading. It's more than the press; It's recipes, case preparation, Cartridge OAL, bullet weights, fiddling with scales and calipers, picking the right powder (or your 3rd or 4th choice because the store is out of your first choices). Beginners want their initial experience to be a good one, and there's no better way to kill a new reloader's enthusiasm then the myriad ways that a progressive press can go wrong out of the box. Progressives require good alignment, testing, and most of all, patience. An experienced reloader already moves with the familiarity of adjusting dies, figuring out primer loaders, and just how much wiggle room they have in their favorite bullet recipe. In addition, Single and Turret presses are considered to be functionally identical in terms of this rating, with the exception that all die elements are held in the turret, rather than in separate bushing assemblies for the single stage press.
For those of you STILL interested in progressives, consider reading this document for comparison (
http://www.comrace.ca/cmfiles/dillonLee ... rison.pdf). Keep in mind, however, that progressive reloading people tend to divide into two camps, Dillon fans and Everything Else fans. This document is not entirely kind to Dillon fans.