I'm fairly well convinced of the value of BIM, but I don't want to make the mistake of letting marketing hype lead me to choose the wrong tool.
I'm no Autodesk fanboy. In fact, I have serious problems with their business practices. On the other hand, I've been using their software since about 1989, and I find their approach to user interfaces very intuitive. It's a love/hate relationship. I love their product, but I hate their executives, marketers, and bean counters.
Then there is Bentley. I haven't had much exposure to Microstation, but I haven't liked what little I've seen. I have heard good things about their approach to customer relationships, but I have also heard bad things about their licensing practices (see Ed Foster's GripeLog). There have also been some negative comments made here and elsewhere about the stability and technical quality of their software.