I seem to recall someone looked up the PN#'s for the shocks & it was the same # for all models.
In my opinion it's not significantly more "off-road worthy" than other models, but whether or not it's worth it will ultimately be up to you.
I pretty much was going to buy a SLE A/T, but then while out test driving some I was offered a loaded up SLT for what I was being quoted for the A/T I was going to order, so I bought it & I'm very happy with it.
Here's my pros & cons on the A/T vs SLT
Seats with red trim are pretty nice, also like carbon fiber trim
Color match mirrors, bumper nice
For me Off-Road" capability was just hype, no real substance like say the ZR2 is.
Main downside for me - Heated mirrors NOT available? WTF GM, this is the trim level it should be offered on for all the rough & tough outdoor types!?!
I never thought I wanted or needed leather seats, but after taking one home for the weekend the SLT seats & "soft touch" trim was really a step up (for me) & was set off nicely by the brushed aluminum trim.
All the chrome trim- not really my preference, but what you gonna do?
SLT rims - Ones of the nicest if not the nicest factory rims available for the twins (maybe I like the optional 18" polished Aluminum rims a bit better).
Heated mirrors - Nice for this time of year in Canada!
Both models have upgraded climate control over lower models & available remote start, which is pretty much a must have for myself & it's that much better when combined with the Remote link mobile app interface!
I went & installed a Superskidz front skidplate & the GM transfer case skidplate (which I may upgrade to a Superskidz down the road). So except for the factory A/T's more aggressive tires vs the SLT (which are consumables) & hill decent control my truck is already as or more "off-road" capable than the stock A/T.
Bottom line both the A/T & Z71 are not really any more off-road capable, their more just appearance packages. If off-road capability is your main concern either buy the trim level that you like best & mod it to your liking or wait for the ZR2, that thing has substance to it, but expect to pay for it also! lol
You added the heated mirrors yourself, right?