If your going to deprime & expand your necks all in 1 step
While your doing your sizing operation, as a lot of ppl do.
Ex.) Reg FL or neck size die (expander ball left in)
Hands down Forster because of the inline, floating, & self centering
Expander ball & decap rod. You'll get much straighter/ more concentric brass that'll last 5-10 loadings if sized properly.
If your going to do each step separately, as many ppl do,
I'd get a redding body die & either a lee collet die or a neck bushing die (redding, Forster, or rcbs g.m.) & a neck expander die & mandrel from one of the better neck turning companies. Along with the obvious universal deprime die.
For seaters the inline systems by redding and Forster sure give the best results. Micrometers make life easier but theyre not at all necessary.
Guess it all depends on how far u wanna take ur accuracy level. If your goal is shooting at a thousand then you'll save money buying the better dies first. Trust me I tried to skimp myself.