I don't have experience with the barrel, but see the video below
As I said, I don't know the barrel & silencer but it appears to claim to be an effective one rather than just a lookalike. If it is then in the video when he takes the back off it would no longer function (but still 'move' the sound)
With it being hollow though I don't really see that it would be effective without anything to baffle the sound
I've had a couple of Gommie suppressors - the first was a plastic tube containing 'baffle' material and my current one is Carbon fibre
Both are effective in that they reduce and change the sound
For the purposes of asthetics, it's a matter of what you like
For the purposes of 'extra accuracy' of a longer barrel, the theory is there if the normal barrel is too short, but I always find pistols gain accuracy anyway with the natural pointing effect of a pistol, and that I wouldn't be looking for more range accuracy from a pistol due to the different ways I play with a pistol. To me it's for easier movement, getting close and in confined areas. If I'm supposedly disadvantaged by lack of distance then that's a factor that makes me enjoy the greater challenge