<edit>The other thing I wanted to add, is that since I have very specific and limited requirements, it should be possible to build something that much more efficient than a system that has to accomodate 1000s of people's different needs. </edit>
And that is always the best reason for doing it yourself. You get exactly what you want. No more and no less. We wanted a bunch of stfuf that osC wouldn't do. And osC did a bunch of stuff that we have absolutely no use for. So I had to write a bunch of code and attempt to integrate it with the osC code structure, and there's a ton of osC code that doesn't even get looked at by the parser. Ever.
And as you say, you can modify it as your needs change. I'm a very ... err .. unique coder. I have a very unique and specific style and I don't read others code well or easily. Editing the osC code was a great deal of work for me, bolting on the functionality that we needed and it involved all kinds of nasty horrible kludges that I was ashamed to write as a coder
If you need a house, and this house has specific needs - 2-car garage, 2 bathrooms, 3 bedrooms, etc etc... You can either buy a generic 3 bed house and tag on a 2 car garage and build an extra bathroom, or you can build the house from the ground up.
Yeah, you can get a house faster if you buy the generic 3 bed house, and you can start living in it sooner, or you can buy a house that already has a 2 car garage, but it comes with 3 bathrooms, one of which you'll never use - And your extensions won't ever truly be a part of the house, because that's what they are.. extensions - They weren't a part of the original structure of the house, and you had to knock down walls and make doorways where there weren't any previously to make them work.
Now, buying a house is a significant proposition, and most people's needs are not unique enough to warrant a totally custom-built structure that serves all their needs, and is built in such a way that it can be easily expanded to serve all of the projected needs in the future as well.
But I know that if building a house was as easy (for me) as writing code, I would have custom-built the house I live in right now. Because then I'd get exactly what I want and need.
Control freak? Me?