Tocoman offers a solution to integrate Revit with etimating tools like Microsoft Excel or Timberline. The application is called Tocoman iLink, which tells that it intended to link the BIM objects with the existing cost databases. It is an extension to Revit, so it utilizes the native format instead DWF or some other file.
Use can read the estimating items into Revit and link them with objects. The linkage is based on intelligent (or dynamic) rules, which simulate the traditional process, but are much more efficient.The software has been used in over 500 real construction projects for BIM based takeoff and/or estimating until today.
Tocoman - BIM based Quantity Takeoff and Estimating
I can second that ilink is a powerful tool. Comparing ilink to QTO is similar to comparing my kids little league team to a proteam. It is still baseball but they should not be on the same field at the same time.
I would also take a look at Vico Office.
It has what I consider the best set of tools for 4D and 5D BIM.
It imports Revit and other BIM formats.
Here's a link: