Green’s Dictionary of Slang

whiz bang n.1

also wheez-bang, whizz bang
[whiz n.3 (2) + SE bang]

(US) any person or thing that is impressive or successful.

[UK]Hall & Niles One Man’s War (1929) 301: That Yvonne person is a whiz-bang.
[US] in W.C. Fields By Himself (1974) 411: Mack Sennett has a story which I think will be a whiz-bang for you.
[US]M.H. Boulware Jive and Sl. n.p.: A Whizz-bang ... Attractive girl.
[US]‘Ed Lacy’ Lead With Your Left (1958) 92: Maybe she’s right about it not being the best job in the world for me, maybe I would be a whiz-bang at something else.
[US](con. 1916) G. Swarthout Tin Lizzie Troop (1978) 186: I am one wheez-bang.