What the blue unit does is a constant chare of 13.8 out. A regular VR will shut off at usually 14 or so and start back up around 12VDC That way it does not over charge the battery. Hope that helps
Here's why I think it is mostly hype. A VR is SUPPOSED to put out constant voltage. That is why it is called a "voltage regulator. VR's DO NOT SHUT OFF they regulate at a set point, about 13.5--14.2 So if it regulates at 13.8, it should be fine.
Someone once posted that the problem is the think blue paint, and that if you scrape the mounting so that it properly grounds, the problem is solved.