MADISON, Wis. -

The leaders of four major health insurance companies in Wisconsin say the roll out of new private market exchanges under the federal health care law will be filled with uncertainty and horror stories.

But they also said during a panel discussion Tuesday that over a series of months and years the problems will be worked out as everyone involved better understands how the new system will operate.

The panel hosted by Wisconsin Health News included leaders WPS Health Insurance, Dean Health Plan, Physicians Plus Insurance Corp., and WEA Trust.

WPS Health Insurance president Mike Hamerlik says there is a pent up demand for health care services and it's impossible to know what effect that will have on how well the Affordable Care Act works.