I had the 170 diesel engine in the VRS Octavia (PD) and the Superb (CR) , both with a claimed 170hp, I tested both stock, the Octavia made 198hp on the dyno and the Superb bang on 200hp with less torque than the Octy iirc. I did later have the Superb remapped but never put it on the rollers as you say the midrange was much better and was more tractable, most noticable difference was being able to pull cleanly from 70mph in 6th which it couldn't do stock
My current petrol 216hp (220ps) VRS Octavia made 246hp stock on a rolling road , and I use the pretty stingy Dyno Dynamics rollers , seems to be a common theme with Skoda's