No, I havent used it before. Im actually new to Autocad. Our company is gearing towards using it for coordination and pre fab.
Which trade were you using Autocad MEP for? If you just purchase Autocad MEP you will find that all of the fittings and equipment are generic. There are a few add-ins for MEP for duct and pipe that add manufacturer specific fittings and equipment. I use the Eastcoast addon and find that it does everything that I need to go from design to fabrication. You can view demos at www.eccadcam.com. There are other addons that do similiar functions in their own way. You will have to research and decide for yourself and your company which is the best fit for you. I just wanted to mention that by itself Autocad MEP is not a fabrication program out of the box. If you can invest alot of time and research you can definately create all of the fittings and equipment yourself. They have a robust fitting and equipment creation program included with the software. You will need to research information on the internet on the best ways to use it. I would recommend Autodesk University. There are numerous free downloads on how to use the content builder as well as Autocad MEP. Just sign up for an account and go to the Online Classes section. Choose Autocad MEP as your software choice and ALL for years. I would recommend the class below for creating parametric content.
AutoCAD® MEP Content Builder: Simplified Workflow for Engineers by Joshua Benoit
http://au.autodesk.com/?nd=class&session_id=7393
Good Luck and welcome to the community.
To find training for Autocad MEP I would search in several places.
1) The user guide has a ton of information on how to correctly use the program.
2) The help file is a great resource
3) There are many videos on Youtube on how to use Autocad MEP
4) www.cadlearning.com has entire video series on how to use autocad and autocad mep plus many other Autodesk programs going back several years and several versions. I would highly recommend at least getting a trial subscription for a month to check out the content.
5) Check out Autodesk University. There is so much information located at this site that many people are unaware of. Keep in mind that Autocad MEP is built on top of Autocad Architecture which is built on top of Autocad. All classes have valuable information in them, particularly autocad architecture classes. Many of the display features and scheduling features remain the same between the programs.
6) Last of all I would check out the book By Paul F. Aubin, Darryl McClelland, Martin J. Schmid & Gregg Stanley called Mastering Autocad MEP. They just released the new publication for autocad MEP 2012. You can purchase it at paulaubin.com or from amazon.com.
I hope this helps.