Since AutoCAD MEP has been around longer than
Revit MEP, I've got more experience with the AutoCAD MEP program. I have been around Revit and was on the scene working for a reseller when Revit MEP came out. I followed it closely for the first couple of years and then just watched from the outside as an MEP consultant.
If you find your firm going to Revit MEP, it's probably because you have landed or want to land a project where it is required. If you have some AutoCAD MEP experience, you will at least understand systems and connections. If you have Revit Architecture or Revit Structure experience, then you will at least understand Revit and families.
Two questions always come up. First, what are the system requirements. For most Autodesk programs you can find these at the Autodesk website. For Revit MEP, I believe these specifications are inadequate for real world use. The second questions is always whether the product is ready for prime time. It's getting better, but it's a matter of question and debate.
You'll find the Revit MEP System Requirements
here.
What I recommend for Revit MEP is that you read some posts in the
AUGI Forums on the experiences of other users. You'll learn some of the following that I gleaned today.
Revit MEP files can be 75-150MB in size. Add to this a possible additional 500 MB in linked models. You may have both a structural model and an architectural model.
You need to anticipate file size and how your network is going to access these files. Network speed and capacity is going to play a role here, not just what computers you buy.
Revit does not yet take advantage of multi-core machines. Rendering is the only portion that can use multi-core as I understand it. Clock speed and RAM seem to have the biggest impact. Seems to be 12MB is the minimum RAM.
When you start to look at your pilot project, you'll also want to visit and discuss with other users different methods that work better in addition to whomever will be handling your implementation. You're going to need help to do this right.
Some firms separate disciplines into different central files while others create a workset per floor per discipline. Most seem to strip the architectural file to decrease the size. You'll want to review the pros and cons of these actions since some methods almost defeat the purpose of using Revit because you lose the ability to connect when you split up to more manageable file sizes.
Here are some threads and resources that I recommend you investigate before you invest in a system or begin a new workflow.
Happy with your Hardware?
Revit MEP Afterthoughts
Revit - Hardware & Operating Systems
Revit MEP Resource Center
Autodesk Model Performance Technical Note (.pdf)
Autodesk Whitepaper on Hybrid MEP Design and Documentation (.pdf)
BlogsRevit GarageThe MEP CAD EngineerRevit MEP BlogInside the SystemCAD ShackThe BIM Bulletin