I've recently purchased the Redding comp seater die and so far I have been pleased with it. I to was torn between Redding and Forster. I ended up going with Redding basically because that's what most are using. You will probably be pleased with either one you get.
Redding does seem to be the preferred brand by more people but not by much. I have used both and both are excellent. Forsters are probably a bit cheaper if you are budget conscious. If you want the interchangeable bushings, Redding's are tough to beat. Forster has some bushing dies, but not the selection Redding has.
Thanks guys I have the basic Redding dies with the micrometer addition on the seater and like it. I would like to upgrade to the bushing dies and have a hook up available for the Forester dies that come with a significant discount. But I want accuracy to make my decision not the discount.
nice thing about Forster is that you can buy the sleeve, and ream it with your chamber reamer. For me the Forster is a little tighter, and seems to seat straighter. Plus there's the 33% Redding tax. Every bad die I've ever seen had Redding written on it
I have came to the opinion that the only way I'll be neck sizing with a bushing die, will be done with a Wilson inline (or similar) die. Just works better everytime. I've got a couple Redding S die sets, and they were OK but not a Wilson (or even close to a Wilson). Have never used a Forster bushing die, so won't comment on them. Still I'd bet the Wilson is better.
Then there is the issue of just how good of a die does one need? You can have the greatest die set on the planet, and use it with a press that's junk. You will get even more junk. Always think in the terms of system.
One advantage to a Forster die is that you can order a non-bushing full length sizer die with the Neck ID custom ground to whatever dimension you prefer. Costs about $15. I've found this very convenient for a .223 Rem die I ordered from Forstner. I had the neck ID ground so that it barely sized the neck any smaller than necessary to hold my .224 bullets. I leave the expander ball in the die and it comes back through the neck with very little expansion. Maybe none. I don't outside neck turn my .223 casings, so this allows me a lot of flexibility in using this die on a variety of Brands of casings.
My measured runout was greatly reduced compared to the former RCBS full length sizer die I had been using previously. The RCBS die was way oversizing the necks, and then pulling the expander ball back thru the necks of the casings was causing a lot of casing neck runout.