Replace vent pipe?

All,

I have my kitchen walls completely opened right now. I have a vent pipe running from roof to the basement for my kitchen sink that is galvonized. This pipe is in fine condition. I intend to replace the drain to the sink, the T, and the lower section of this drain pipe. I'm assuming I can join this to the existing vent using a neoprene sleeve or similar compression connection. I've pulled all my permits, etc, as part of this process has also been replacing the cast iron portion in the basement with PVC.

My question is, the wall is open and will be closed - is there any compelling reason to just replace the whole vent pipe with PVC and reseal on the roof or is this just extra work with no real benefit?

Thanks!

-MaxProphet

Typically the galv. above the wet portion should be in pretty good shape and can be connected to the new plastic drain with a banded coupling such as a mission or fernco proflex. Its your call you're on site to evaluate its condition.