I'm thinking this may be illegal even though you need a tool to adjust the length but not sure.  Has anyone seen or purchased one of the WOA stocks?  I really like it and wouldn't mind getting one.

 

http://www.whiteoakarmament.com/xcart/home.php

 

That looks like a rifle length tube, so I fail to see how that would be an issue, you can only really make it longer, not shorter, but .. well .. this is NJ so who the hell knows. I would call that adjustable not collapsible, kinda like the  Magpul PRS. 

the PRS is a stock with an separate adjustable cheek rest and butt plate.. the stock is fixed..

 

the notion that a stock can only be made longer is not a valid one.. because you can make it longer.. but then once longer you can shorten it...

 

IMO it is very unlikely that the stock pictured would get you into trouble.. I am not sure if the "stock" adjusts because I am not sure what part of it IS the "stock".. the spirit of the law is likely not to ban an item like that.. additionally the fact that adjustments can not be quickly made probably further reduce any issues.. thats not to say it could not be questioned.. but I find it very unlikely anyone would take up actual issue with that thing...

Just get a PRS... Don't need mods. Just picked one up cheap for my M6....

Going to set you back a bit because you'll need a rifle extension buffer kit.

 

I have a PRS but it's an spr style rifle and it's too heavy. I was going to use the PRS for a long barreled 6mm that I'd like to build.

I dont think that is a good style of stock for pretty much anything but high power type shooting.

 

The PRS is heavy but it balances heavier barrel rifles. If you want something like it but lighter, take a look at the Luth-AR stock.