I have a number of theses strip soft boxes and I use them for certain jobs. Unless you have specific requirements for theses light modifiers, they may not be worth the investment because they are not really intended for general usage. So here's the information that may prove helpful for you.

In my commercial work, I use them for creating elongated highlights on beverage bottles and certain types of glassware. This works well well when the strip light is placed at 90 degrees to 135 degrees to the camera/subject axis. I also use a strip light on a boom arm, over the set, for panoramic-like food layouts. Most of the time, however, a standard square or rectangular soft box can do the job as well. The addition of a go-bo or black flag can be used to thin out the light beam from an ordinary soft box.

In portrait work, the strip light can be use on a boom arm, overhead and slightly behind the subjects to provide a nice hair light for group subjects.

As per size; the rule of thumb for softness of lighting is that the closer the light source is to the subject softer the transition from highlights to shadows will be. Larger soft boxes will tend to yield softer lighting at slightly grater distances but they too will yield considerably harder light as the are moved away form the subject. If you are working in a limited space as smaller soft box may do the job if it close enough to the subjects such as as the distances you may encounter in a table-top commercial shoot. If however you are shooting a full-length fashion shot or a larger or taller object you may require a lather soft box to provide adequate coverage and softness at a grater distance.

Strip lights, generally speaking, do not make for good main lighting for portraiture because they create thin vertical catch-lights in the eyes which look kinda strange, however, they can serve a good “kicker” or accent lights when place at about 135 degrees to the camera/subject axis. This can be effective when the main light is a standard soft box or a parabolic umbrella lighting unit.

Single or double kicker lights can be applied to theatrical portraiture or body-builder type shots in which case the strip lights would serve you well while using a standard soft box or parabolic lighting unit for a main and fill light sources. When using lights for kickers ,at steep angles of incidence, it is important to make sure that exposures for theses lights are in balance with you main and fill lights. The kicker lights may have to be powered down because at steep angles of incidence the lighting tends to be stronger and more pronounced.
I hope this helps and good luck with your lighting experimentation. Practice makes perfect.

I wonder how many "hate crime" charges have been filed in total? I see the guy's plan to get his act into the news, but being white and male, he was a total idiot to videotape this.


Federal authorities charge white ‘knockout’ suspect with hate crime

Federal authorities said Thursday they have arrested and charged a Texas man in connection with the “knockout game,” accusing him of a hate crime for targeting a black man for a vicious street attack.

http://www.washingtontimes.com/news/2013/dec/26/federal-authorities-charge-white-knockout-suspect-/

Does it also "buzz" while it flickers? Have you been playing with the custom functions? I ask because I also had a problem with mine. I finally discovered I had set the custom function for the modeling flash to activate by the test button--the red "ready" light. Every time I pushed that button I got a couple of seconds of "strobe" effect and a buzzing. Very disconcerting.
I don't have my flash or manual with me, but it is fairly straightforward. There is also a way to reset all custom functions to factory default.