Does the Scorpion pistol work as expected with mods and ammo powers?

I've spent a little time in the firing range trying out my collection of weapons, which I've mostly ignored so far, and have spotted the Scorpion pistol. Unlike most of the game's weapons it shoots little timed sticky grenades and is therefore my new favourite toy.

I'm wondering, does it work with the ammo powers (Cryo in particular)?
And if so are they triggered on impact or explosion (or both)?

What about the weapon mods, I suspect the 'piercing' mod in particular is a bit pointless here?

The Scorpion freezes enemies almost every time upon IMPACT with cryo rounds. Then the blobs blow up, shattering your enemy into a lot of pieces. Max out your Scorpion to reduce the weight penalty. I haven't tried the fire ammo, but who cares with results like this?

Yes, ammo powers will work with the scorpion, and some will be extremely effective in combination with explosions caused by it.