I do not have hands-on experience with 7 STW, but I have with .30 Gibbs without any issues. I am happy with it. Are they good high-quality stuff? Qual Cart quality is no Lapua, ADG, etc., but they are good.This brass is currently not available, but if/when they make more, is it good high quality stuff ?
If you do not mind not having the proper head stamp, Peterson makes a blank belted brass you can form, https://www.grafs.com/retail/catalog/product/productId/88972.