This won't gain me any popularity but once again:
Pinball is not a safe investment. Buy a pin because it's cool and you enjoy playing it.
If you see things that way, additional versions of already released machines is just icing on the cake.
I doubt I'll have any trouble selling my Met Premium at a fair price simply because the DD Custom edition is available.
Seriously: those of you still complaining about WOZLE: enjoy your game or sell it and be done.
Have they really dropped in value now that you can buy a red one? Seems to me that WOZ pricing is more affected by the fact that half of the pinball players in the world just don't appreciate the layout of the game and/or enjoy playing it.
Overall value seems to be affected primarily from the rating and fun factor of a game. Tron and ACDC are great examples. Had Met seen the code update shortly after release, I'll bet they'd be worth more too.
Edit: great point Hank. I'm not in agreement that new versions should be produced when others are still waiting for their prebooked LEs. Just saying that more versions is a plus, not a minus.