Marmot Dri-Clime stretch pants

What will you use them for?

You mention bushwacking – if for that purpose, then it better be cold or you'll sweat to death. Driclime offers a good bit of warmth.

If for in camp warmth, then you're good to go. Even then, only if you don't already have puffy pants or hiking pants and a base layer, as this combo will offer the same warmth, +/- at probably less weight and more versatility.

As for wind, you can go a lot lighter with Montbell, Montane, or other wind pants.

A pair of light windpants definitely deserve a place in your pack if your dealing with colder weather in windy environments.
If you plan on bushwacking in them, you should get a heavier pair and use them as your main hiking pants. I've found some cheap wind pants at thrift stores, usually marketed as running pants. Some of them are in the 7-8 ounce range with nice sturdy fabric.

edit: I just realized that these pants are 9 oz and a stretchy soft shell material. In that case it's hard to tell how tough they are.

I should have stated the expected hiking conditions.
These are for cold windy, mostly dry conditions with light rain thrown in sometimes.
They are two layer with an inner wicking layer that is well proven.
Yes they are pretty light and pack small.
The outer shell is "100% Polyester DWR Ottaman 2.2 oz/yd"
The inner NTS layer is a sort of paper thin micro fleece wicking fabric.
They are athletic fit with side stretch panels. They were designed as cold weather running/hiking pants and alpine approach pants.

The normal hiking pants would be RailRiders Adventure pants.
Baselayer in cold would be Icebreaker Bodyfit 200 Merino Midweight bottoms and lightweight top. Also used for sleeping gear.

These would be for places such as JMT, CDT, PCT and the Cascades where wind pants would be a good idea to have. (Although I rarely see them discussed here).
I could skip them and use Patagonia Houdini wind pants instead at 3.2 ounces,
or I could leave the heavy Railriders at home and just bring the nylon hiking shorts + the DriClime pants. I could not treat the DriClime pants with permethrin, unlike the Railriders.

I wonder how Epic fabric based pants would hold up bushwacking?

I was reading through segments of "The Complete Walker" by Colin Fletcher yesterday
and he raves about DriClime fabric for wind shirts.
That shows how long the stuff has been around I guess.
It's looking more and more like these pants should stay home unless an alpine trek is on the menu where they would serve as full time pants.
A lighter pair of Houdini wind pants or equivalent might be better for the cascades for example, where they might spend the whole time in the pack.

I love, love, love my driclime jacket and use it all the time, both for backpacking and around town use. My driclime pants however have almost never been worn. They are simply far too warm to use for backpacking. Great ski pants though.