I've had two DD50's, and still have one. I paid about $1500 for each of them and sold one of them for almost $3k so I figure the one I have is a "free amp" now.
I don't really understand the hype, it's not a bad amp but it doesn't blow my socks off, but some people really seem to love them. And I will say, it's a uniquely designed amp and there isn't anything else exactly like it, so if you just have to have the DD tone, you don't have many options as far as the "big" heads go.
It's also worth mentioning I guess, but the single channel OR50 is one of my favorite Oranges, super flexible amp and I love it every time I plug in. The DD50 does a damn good impression of that amp if you can keep the gain in check. The key piece the DD is missing is the "punch" control (it's just a presence knob). But the DD's channel A can be really sweet if you are careful when dialing it in. Channel B has the "shape" control which is hit or miss, you either love where the frequencies sit or hate it and can't find a spot you like on it anywhere. Basically what I'm saying is, just because it's called "dual dark" and marketed like a metal amp doesn't necessarily mean it has to be dialed in as a super saturated doom/metal monster. It actually does the classic orange fuzzy-rock sounds really well.
They are pretty clean inside. They use Demeter transformers. Here's the inside of my DD50 from 2017:
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Oh and here's the transformers (well, two of them anyway)
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