Does anybody know anything about these?

I may try one but don't know if I should neck size or full length size.  I have a ton of once fired Lapua from my bolt gun that needs to be resized.

I'm trying to find the least labor intensive way to reload my brass for my bolt .308.

It sounds like your brass is fire formed to your chamber.  Unless the reloads will be used in a semi-automatic or different bolt action rifles, I don't see a need to full length size the brass.  

I neck size brass fired in my Savage 10FCP with good results.  I don't trim the cases to "trim length" listed in my reloading manuals.  I trim to a length halfway between maximum case length and published "trim length".

Redding Custom Dies are "One Of" dies.

The best suggestion for you is this.
Buy the Redding Type S Match Neck Die Set #38155
This comes with
Body Die this is like a FL sizer die with the ability to size the neck portion of your brass
Type S NK Sizer Die (which you need to purchase the appropriate bushing) for Lapua brass 0.336 should be spot on for 0.002" springback)
Competition Seater Die

You can only neck size for so long before you have to bump the shoulder.  There is no finite # of reloads to say it is time.  Your brass will tell you.

Another other option
Buy the Redding Type S Match FL Die Set #36155
This comes with
Type S FL Sizer Die (which you need to purchase the appropriate bushing) for Lapua brass 0.336 should be spot on for 0.002" springback)
Competition Seater Die
You then buy equipment to set the dies bump the shoulder enough allow for reliable chambering about 0.002"-0.003"
This is smart of competition shooting and hunters...as you do not not want a case to hang up at a bad time

Based on this get the Forster Bump Neck Bushing sizer.

They size the neck and bump the shoulder back, they do not touch the body so no lube is required. With it, sizing takes no more effort or time than decapping.

I have used this die solely for my .308(Lapua) for about 10x firings, 6x firings for my .223 AR(Lapua),  it works great, full length sizing is not required considering my max psi loads.

I wish the made them for Grendel as I have to used a Redding for that.

I just bought a rifle chambered in 6.5 Creedmoor and am in the market for reloading dies.  I'll have to look into the Forster dies.

Forster makes great dies and the price point is better than other brands, but it is tempered by limited selection.
And, not every cartridge has the Bump Die / Kit or Neck Size Die either.  Their mounting of the expander ball higher on
the decapping rod helps minimize run out.

The only concern is that at times they vendors are out for months at time in various calibers.