I think that some people find the full-length version a bit too heavy at the forend.
The carbine is better, but still heavier than the AAS410.
But the HW is solidly built. Mine have shrugged-off knocks that would have upset a S410 (I know because I've owned S410's before that couldn't take much of a knock without losing zero - I replaced them with HW100K's).
The HW also has a regulating mechanism, which means that you don't need to look for the pressure sweet spot.