Being able to do 3D modeling to earn a living is a wonderful thing, IMHO. It takes a lot of effort, a willingness to adapt and learn many new things along the the way and quite often, something unique. I also think it requires more than just using MoI, as awesome as it is. Think of a tool box - it has more than one tool to suit different requirements. I think even Michael Gibson stresses that additional tools are required, since MoI was not created to be the one and only tool. I believe he says it is a tool to allow ideas to be laid down quickly for development further along in more suitable programs.

I started out learning one CAD system on my own when I needed some illustrations for a project I was doing for myself (book illustrations). I stumbled across TurboCAD and fell in love with it. There was very little in the way of tutorials to learn it by, so when I got proficient I started to create unique comprehensive project tutorials (200-300+ pages). At first I gave them away, but was soon encouraged to market and sell them. That was a number of years ago and I have continued to do this as a large part of my business. This is the unique part I was referring to. It was a whole untapped market where I developed a name for myself.

Those tutorials brought a large number of visitors to my web site and even a few long term clients, who at first thought they might like to learn TurboCAD to help in their own business. Some found that it was way more intense than they had expected and just asked me if I would do the work for them. I said yes each time and expanded my business to include graphics and design. To continue to meet the many varied needs (3D trade show booth visuals for one client, engineering & manufacturing drawings and product renders for a couple others and Ad work for yet another) I have had to learn many software programs and I use them all continually, many overlapping with each project. I came in knowing TurboCAD, I then learned and became proficient with Photoshop, Illustrator, InDesign. I then had to learn SolidWorks as one client needed me to do so (they supplied the software, thank goodness). I also picked up MoI to help fill in a couple gaps and although I don't get to use it as much as I would like, I know the power it has. MoI exports well, so I can and do bring things created in MoI to other programs.

I guess what I am trying to say is - put in the effort to learn lots. Don't be afraid to try new tools and don't fall into the trap of thinking you can do it all with one tool. Sometimes it doesn't matter what the tools are but rather the output. Can you meet the needs of your clients? It doesn't hurt to know at least one of the big name programs like SolidWorks, as that can get your foot into doors (as an employee), but more often than not you will not know the 'right software'. But as a freelancer, you can use the not so well known software such as TurboCAD or MoI and be okay - as long as you can deliver and file share when required. You will require a software that can do the detailing and a CAD application, for one, can help you do that.