First off, if it's a T6, it will have Dynamic stock (unless customer ordered touring which is pretty rare).
I'd say the easiest giveaway just by looking is the presence of the 18" Sleipner wheels. Since most owners of these cars aren't going to change out wheels, if a T5 (or T6) has those wheels equipped, you can be certain it has Dynamic.
While it's hard to explain, when I was searching for mine, it looked to me that the Dynamic-equipped cars had a slightly more aggressive stance than the touring-equipped cars. Look at enough of them and you probably will be able to tell.
If you're actually driving the car, go into the Sensus menus and look for the adjustable steering force. If that option is there, the car has Dynamic.
Your dealer should be able to pull the car's build sheet, if all else fails.
Adjustable Steering Force is determining how heavy the steering wheel is right? Light, medium heavy?
Canadians have that on their S60 T5 Level II.... But I'm pretty sure Canadians were shafted with touring suspension and no option for dynamic suspension. At least we didn't get to choose when we bought the car.
I've got a set of used dynamic chassis springs and rear shocks from my T6 when I changed to the R-design suspension. Let me know if you are at all interested in them. IIRC I think you might also be looking at a new front struts between the touring and dynamic chassis (t6 dynamic front struts and r-design struts are the same), and some bushing changes.
Separately, I would highly recommend that you look into the IPD rear anti-sway bar. It is a very worthwhile upgrade.
IMO there is a huge difference in ride quality to tell if the car has dynamic or not. Just go over some small bumps in the road. I guess you could order the touring chassis with adjustable steering and rims but I think most people would go for the freja's instead.
Is that the only difference between the touring and dynamic? struts, shocks and springs? Then the R-design has different struts, shocks, springs, bushings and strut/cross stay? Are the sway bars the same on all?