Gas tube length effects on suppression?

I saw an ad for a 'pigtail' gas tube that will lengthen a pistol-length gas system to carbine-length, ostensibly to reduce bolt-slamming, et al.

Will using such a tube affect/improve reliability when shooting with a suppressor installed?

From the very limited testing we've done with such a thing on a 556 carbine, it does reduce the gas drive somewhat.

Depending on the application, it's probably better to relocate the gas port further out and use a standard tube.

Thank you, sir!