As far as the history of Xiao Zhuan's pen is concerned, at first, the ancients used wolf hair because it was hard and expressive, which could reflect the toughness of stone carving. Later, people gradually used wool because it contained enough ink. Every sheep has its own advantages and disadvantages. Beginners suggest using two brushes. As for the proportion of wool in the doubled both brush, you may need to try several brushes with different proportions before you can determine which one is right for you. This is different for everyone, so there are different kinds of pens on the market.
Personally, I don't recommend the long peak pen recommended upstairs to beginners, which is difficult to control. You can choose a peak of 40+.
* * * Give it a pep talk ~