Tesla obviously put time and effort into making the HPWC look cool, in addition to its function. But it doesn't look so sleek when you install that big boxey subpanel next to it. As I look at various user installations, I see some have it and some do not. When is the subpanel needed, and when isn't it? Thanks to efusco for posting that image. Note: I don't know if that's Teslas official box or not (looks like it may not be).