Most helpful is the real world contents and their prices and specifications. The catalog of items is most of the times very accurate. Also the cost of labour can be included based on the skills of labour. Also its inter operability with Revit fabrication is very good. You no need to model everything inside fabrication EST mep. If you have your 3D model in Revit MEP fabrication, then you can bring in that model in Fabrication EST mep and do further processing. Not only Revit you can also import your 3D model from AutoCAD MEP. Review collected by and hosted on G2.com.
There is very less or no inter operability between other than autodesk softwares for example aecosim or microstation. But in such cases we can use the IFC format with some modifications or work-arounds. Review collected by and hosted on G2.com.