I use the aluminum needles, but when I was a beginner, the yarn sliding on the needle was my worst enemy, lol! My biggest piece of advice would be to keep more than two skeins of any one dye lot in stock. I always end up needing a lot of one color. If you offer the option of special ordering large quantities, I bet that would be appreciated by your customers for larger projects. The local craft store here will not do that, so you must change the color pattern in what you are working on to correlate to what yarn you can get several matching dye lots on. My favorite yarn is "I love this yarn". It is soft, affordable and easy to work with. Good luck!!!!