Before you make a decision about whether or not to use commercial yeast, you should listen to this podcast:
Hint: The first yeast to interact with your grapes isn't the one you want!
I have been making wine for a long time and keep losing the angled metal tabs that allow my #25 wine press to ratchet. I'm pretty sure I'm hiding them on myself. Every few years, I have to buy new ones. How does anyone else deal with this problem?