He's cheap and cheerful, and you can do whatever you want with him without suffering major regrets or guilt.
I had two DX08s on pre-order and eventually ended up cancelling both of them.
The '89 movie wasn't a big draw, but I liked the idea of a Nicholson Joker, even though I've always thought of him as a fake, dead Joker.
Nolan's Harvey Dent was a fake, dead Two-Face, but I ended up with two of them. In my mind figures have a life beyond their brief time on film, but Nicholson was never going to fit with anything else. I had a few small regrets later, so when Mars offered a cheap stand-in I went for it. Even now he won't fit, so will probably end up with '66 Batman and Robin in lieu of Cesar Romero - my favourite Joker, and the one that still creeps me out!