I have a couple pairs of the Carhartt double-front jeans in green that I got on sale from Baileys--just looked last night and found they're no longer there.
I think Carhartt stuff is over-priced in general, and I only buy their stuff when on sale or reduced rate thru ebay. My insulated overalls, for instance, are Walls brand, and every bit the equal of Carhartts. (They're also I-don't-know-how-many yrs old, patched in the knee, but still good to go.)
For double front jeans I like the WildAss jeans. That's my everyday wear in the woods, been wearing them for some years now. $30/pair on sale thru Bailey's. I liked the Prison Blues too (I think that's the name), but found the fit of Wild Ass suits me better.
The problem I run into is that for several years now all my pants shrink in the waist through the winter months. I've worn 34 X 34 pants forever, but now I need 36 X 34 thru the winter. Warm weather and more work gets me into my normal size.