I am looking for a light kit and have seen some of the fluorescents. After seeing them in person, are the fixtures themselves any different than an ordinary shop light? only difference being that the tubes are daylight balanced? I am fairly good with metal working and i could easily rig up something that would work in the same way, 8 tubes per light.
The advantages of using professional fluorescent lighting instruments and globes (like those made by Kino Flo) are many.
First off, regarding the globes. They are designed to be of photographic quality, meaning that they burn at predicable color temperature; either 2900K, 3200K or 6000K. This allows you to choose the appropriate tubes for the particular scene. In addition these tubes are rugidized and constructed with plastic overcoat so that in the event that they do break from transport or rough handling (which is inevitable, the broken pieces are contained within.
As far as the fixtures themselves, the lamp head is designed, engineered and manufactured to maximize the effect of the tubes with properly designed reflectors and grids to direct the light without spilling in every direction. The harness and cables are built with usability and safety in mind to protect the operator and the subjects who will appear in the focus of the lights and finally the ballasted are specially designed top operate at higher frequency that normal fluorescents so that the output is maximized and they do not flicker at normal framerate and shutter combinations.
Kino Flo in particular has been at this for a long time and they come with a lot of experience in the motion picture and tv lighting business. Their catalog has continually increased as new lighting objectives come into play and each new product builds on those before. All this puts them at a tremendous advantage over someone who wants to save a few dollars by building their own lights, and their prices are quite reasonable to boot, especailly when you consider how long their units last and their resale value if and when you ever choose to part with them.
Your best bet would be to watch eBay patiently and purchase some used Kinos when you can there.