The common verdict is that they should be used on an as-needed basis. No need to run them all the time, as they'll kill beneficial stuff in your water column as well as parasites/etc...
Do a search on this forum. You'll get more than enough information. I'd have to say that a majority of people do not run UV 24/7. Alot of people have them but only use them when it is absolutely necessary. Some people just run UV on QT Tanks. The latter makes more sense to me.
I think that a proper QT regimen will help guard against disease outbreaks.
No problems at all about starting a new thread, you found the search eventually...Bu all means, ask anymore questions you might have, on this thread...
Look at it this way...you just helped someone else find more information on UV sterilizers when they search for it.
Don't worry about redundant threads either. I'm pretty sure one of the threads that you will pull up when you do your search will be one that I started months ago. I too did not rely on the search function until recently.
Never been a big fan of them, myself. Most setups aren't efficient enough to do a good job of parasite eradication (nor is that actually possible in a tank that is infected, since it isn't 100% effective). It does, however do a great job of keeping the water clear, further degrading normally refractory organic compounds, and killing unicellular algae and bacteria.