I have them all. The Flashman novels are great, amusing reads.
The Flashman books are also excellent British imperial history, if you pay attention to the footnotes. As you know, the more outlandish the event, the more careful Fraser is to document it. He takes care to sketch both sides of the big historical arguments as well, sometimes via disputes among characters, sometimes through Sir Harry’s authorial commentary, and sometimes in footnotes. If it’s contested terrain, Fraser finds a way to discuss both sides.