I have no experience with the SuperTuck. But I do with the Walther P99AS.
It is just slightly larger in grip length than my G19.
It is a great gun, probably one of my best, but heck I say that about all my guns.
I will say that I like the decocker on the slide and the fact that every time you pull the trigger it actuates the striker, it is the only striker fired pistol I know of ( though there may be other ) that is like a DA/SA pistol. Rack a round in to the camber and the pull is very easy, if it does not fire you can pull the trigger again and it will strike the primmer again. Not just once like a Taurus, but every time you pull the trigger.
The second pull is only slightly heavier than the first. Really great gun.