Menace is a horizontally scrolling blast-em-up, it's almost the definitive example of this gametype infact. The idea is that you're the pilot of a lone ship with orders to destroy the planet Draconia; six "very different" levels with all sorts of baddies trying to kill you good.
Back in the late eighties, I remember some friends would sit playing these games, autofire inevitably enabled, blasting through level after level of slightly different coloured, or different shaped nasties. To me, it all seemed a bit like a semi-interactive demo, with very little of interest actually occurring, "Oh look, Stew's blasting pink sprites now." To be fair, it is all pretty competently done, for the year (1988) and the bolt on goodies like extra lasers, more speed, and outriders do give the game some extra, oh, all right, depth. The music is quite nice too, if a bit dated, kind of like early Kraftwerk, not what you'd expect to hear in a game these days.
A reasonable enough game of it's type, then, but not outstanding. I'd rate Katakis over this in pretty much all departments. Having said that, if you like this sort of game, you may feel it deserves a place in your collection.