Retirement Plans and Acquisitions

Two companies of comparable size are merging, but have reached a snag in their negotiations over retirement plans. Company A has a traditional management style, and an older, long-service population. It also has a final average pay, defined benefit plan. Company B has a slightly less traditional management style, with a younger, shorter-service population. Company B's retirement plan is a 401(k) plan with a moderate company match plus a discretionary profit sharing feature.

Plan cost to each employer is comparable on a cost per employee basis. It is management's goal throughout this merger to have create a unified culture that will better represent the focus of the new company, and a single retirement plan structure is consistent with this goal.

What are the obstacles the merged entity must address to create a single retirement plan structure that meets this goal?

If you were hired to solve this matter, what would you propose? What would you avoid? Which approach, defined benefit or defined contribution would best address the overall expectations of the new, merged company?