Pros and cons of undercoating a vehicle?

[JoeH]

bobinmurphy wrote:
Highly recommended if you live for drive in areas which use road chemicals (like salt) in the winter.

Except if it isn't done right the undercoating can actually make things worse by creating places where water and deicing agents get trapped. Corrosion in those areas can be greatly accelerated.

One of my brothers worked as a mechanic in a shop that did undercoating. Got lots of pressure to do it quickly, not necessarily as directed by the manufacturer. Later he worked in a salvage yard, showed me more than a few vehicles in for crushing with badly rotted sections partly held together by the undercoating.