Is Aus-8 a good knife steel?

The answer is yes and no. Depends what type of knife and its designated use.

In general AUS8 or AUS-8A, which is alternate name form the maker to state "annealed" product is a decent stainless steel and works best for small/medium knives used for light cutting.

In other Words that is not a good steel for the large knives, sWords etc.

Made by Aichi steel (Japan), similar to AISI 440B steel.

Exact chemical composition and comparison with 440B and other related info in the links.