I'm in pastry school at the moment. The start-up kit that I purchased through my school came with a huge variety of tools: a complete knife kit (however, they're Mercer knives. I was expecting something a bit higher quality. That's not the point, though), pastry cutter, a microplane zester, 12-inch tongs, offset, and straight spatulas, a nice sized pastry tip kit, and tons of other stuff. Unfortunately, they only gave us these crap cheap disposable Wilton pastry bags, and, seeing as how we're on week eight of the term, I'm nearly out. Naturally, I'm looking for new bags -- reusable, this time. My question: What materials make the best pastry bags? I've seen nylon and plastic-coated canvas used, but I'm sure there are others out there. What brands do you all prefer? What size should I get? I want to find something that will really last me through daily use, and I'm just not sure what to buy, now that I'm faced with so many options. So, what do you prefer?