[cobrashoch]

B.Smith - Your experience's reflect my own. It's been my experience that if a live axle is rough riding that most times it will be in a overspring situation or the shocks are too stiff. Most times it's both.
A irs has advantages in weight, handling and ride quality, only when the road gets very, very rough. Suspension travel will come into play then. But then again most of the irs setups I've seen are of the stock factory variety and the stock stuff usially has the short arms and limited travel in the first place. So yes, a irs setup can be made to be lighter than a live axle. In most cases that's the only "practical" true advantage they have, unless of course you are running the popular "full" Jag setup, then you loose the weight advantages with it too. IMHO.
cobrashoch