What shocks should I go with?

[Project1970]

Well, after 50,000 miles (and especially so with less weight up front, courtesy of the LS1) the Belltech Nitrodrops are showing their age. I've never been much of a fan - the rear end bounces and bangs over stuff, and the front end takes way too long to stop again after a bump.

So, I need new shocks for my truck. For those who don't know, it's a '70 GMC, half-ton, two-wheel drive, with leaf springs in the back. It's also lowered 2.5" in front (spindles) and 4" in rear (springs). Interestingly enough, many catalogs just don't list the '67-'72 C10; but most list the '73-'87 C10. Every catalog that I've seen both in, lists the same exact part numbers for the leaf-spring '67-'72 as they do for the '73-'87 - so a shock available for either would be fine.

Here's what I've come across as available so far:
Edelbrock has the IAS shocks...$75 apiece from Jegs.
Koni has the 'Koni Special', $86 apiece from Jegs.
KYB has the GR2, the Gas-A-Just, and the Monomax, from $30 to $80 at Jegs. The GR2 appears to be what Early Classic has switched to from the Belltechs (my spindles / disc conversion / rear springs are Early Classic pieces).
Bilstein has the Heavy Duty, $60 apiece from Autozone.

Which of these is the best idea, or are there other shocks I should consider?