Sidearms is one of the fastest-paced games ever for the Turbo, up there with Override on the PCE. I'm convinced that the game, like SonSon 2, was secretly (in part or wholly) programmed by Capcom and handed to NEC AV for release. Music rocks more than the shitty arcade tunes and even more than the CD ver.
A great introduction to simple shooters, if not totally representative of the "Turbo" experience like Bonk and others are.