pros and cons to steering dampners?

It stabilises the bike, no more .

I bought my SD second hand. It came with an LSL steering damper.
I'm very happy with it, can't think of any cons
Damping strength is adjustable
Example: http://www.twinshack.co.uk/prods/783.html

Bought a second hand LSL damper and worth every penny when going for it down my favourite back road routes

No cons

con: costs extra money

pro: stabilisess bike heaps and seems to help on landings on long held high speed wheelies