Anyone running QA1 shocks, or other adjustables?

[68GMCCustom]

As the title reads....anyone running QA1 shocks on their 67-72 trucks?I've found that not only do they offer their base non-adjustable Stocker Star shocks for '67-72 C10's... they offer single and dual adjustable models and now even a Drag "R" model is available for the front. Anyone running them? I was surprised to see they offer up a full set of options for these trucks.

For the front I'm looking at the double adjustable TD405's:
Double Adjustable Stocker Star Front Shock
GM
Compressed Height: 10.13"
Extended Height: 14.00"
Upper Mount: Eyelet
Lower Mount: Eyelet
Applications:
1963-87 Chevy C-10 Pickup
1988-00 Chevy C-1500 Pickup
http://www.qa1.net/suspension/street...ker-star-shock

and the TD513 for the back:
Double Adjustable Stocker Star Rear Shock
GM
Compressed Height: 11.63"
Extended Height: 17.00"
Upper Mount: Eyelet
Lower Mount: Eyelet
Applications
1967-72 Chevy C-10 Pickup (Coil Spring - but they offer one for leafs)
http://www.qa1.net/suspension/street...ker-star-shock

wondering how they measure up and if the double adj. are worth the extra bucks versus the single adjustable shock on the rear. I'm guessing its a noticeable difference in front between the two...or especially when compared to a non-adjustable.

Or are there any other quality adjustable shocks out there that fit our trucks?