What are these strip-box things? Simply put they're long skinny softboxes. Traditionally these various shaped soft boxes are used to control highlight shape on shiny stuff. Well they are if you're into studio still lifes and product shots. On the people side of the equation they're a nice hair light for one subject and definitely the ticket for more than one person in the frame. Similarly they're great as kickers to but a subtle edge on a subject to pop them off the background without being over the top.
The point is they're typically thought of as a secondary light of some sort. Being narrow they're far easier to control spill. Always good for a secondary light but also useful as a main light. If Im going to use something remotely soft I swear half the time I'll grab that 1 x 3 striplight instead of soething bigger with more spill. I've only seen maybe one other person use the Atomic Canary's stripbox as a main light and he's there 24 x 7.
Give it a whirl as a main light. I was in a hurry making these couple of unplanned frames and wanted to mess with something a bit dramatic. I also wanted something that I could use a bit farther away without lighting up the entire back wall. The strip box and a flag were the ticket to play with a quick concept. Truth is I wanted to put one subject against that bright spot and the other against the dark but didn't have time to play with the angles. Sure bring some fill into the equation if you don't want dense shadow but definitely try a few of the less used lighting modifiers laying around for use at the studio.