I think Virginia is the only state to recognize an online training class (may be wrong). From what I've read it takes approx 90 min to complete.
As far as being credible... I may be old fashioned in believing in actually having to handle a handgun during a CCW/CPL class.
Another issue may be reciprocity (other states honoring your CCW/CPL)... most states require a certain amount of info covered plus range time, which obviously isen't gonna happen in 90 min.
My greatest concern is if you are actually involved in a defensive shooting and the family's lawyer asks about your training regarding your CCW/CPL permit... wonder how that may effect things.
Obvious downside is watching a video leaves no opportunity to ask questions or clear up something you may not fully understand. I know our legal section raises many questions & hypothetical scenarios. The legal section... including how to deal with police if involved in an actual shooting is the most important part of the class, and should not be "glossed" over for time constraints... for it can keep you out of prison.
Just my thoughts on the whole online deal... to each his own though.