I rate it very good.

There's nearly 50 Chan films, most I've seen, and they run enjoyable to irritating. I like the ones with Mantan Moreland the best. Much better comedic relief....more than son #whatever.

They mostly run about an hour.

I'll just list a few I give highest praise...

Charlie Chan at Treasure Island (1939)
Black Magic (a.k.a. Meeting at Midnight) (1944)
Charlie Chan in Paris (1935)
In Reno (1939)
Sky Dragon(1949)
At The Olympics (1937)
Charlie Chan In Shanghai 1935
Charlie.Chan.in.Egypt (1935)
Charlie.Chan.in.London.1934
Dark Alibi (1946)
The Chinese Cat (1944)
Charlie Chan's Secret (1936)****

Those I rate 3 and a half to 4 Stars