I replaces the shocks on my Envoy about 4 years ago with Monroe SensaTracs. They came with Reflex stickers on the front struts. I also replaced the strut mounts at the same time but used the stock springs. I have been completely satisfied with the ride quality. Mostly paved roads, but I do take it on gravel dirt roads regularly to go fishing and they handle that just fine as well. No noticeable loss of ride quality yet. With the OEM shocks at 120K kms, they offered no damping. 4 years, and 50K kms on the monroes (man, i don't put too many miles on this thing) and they are still doing fine, no extra bouncy-ness.
I also tow a 3300lb travel trailer, and the Monroes, with the rear air springs, handled it very well.
Now my air suspension is failing and I'm switching to coil springs which means I need new rear shocks. This time I am going to use Bilstein HD's as they get very good reviews from anyone who has put them on their GMT.
I am also experiencing about an inch of sag on the passenger side, and I may go ahead and replace the front springs, and switch to Bilstein's in the front as well.
I ordered Raybestos coils from RockAuto for the rear, and I am thinking I'll do the same for the fronts (EXT/XL springs for extra support).