I agree. My kids are absolutely loving/thrashing Flash at the moment which doesn't even come near a mid range DMD in value. When I had DMD's, my kids hardly looked at them. Sometimes a machine can have too many bells and whistles for it's own good.
Glad the kids are enjoying the game -
Two points here ;
1 - DMDs are more of a novelty for kids. They find the central "toy" and that it all that will hold their interest. DMDs are too complicated for kids starting out of pins. My son loved Jurassic Park for the T-Rex toy. There are only "so many times" you can watch the T-Rex pick up the ball. But sometimes I have to pull him away from Medusa or Paragon. He was actually in tears when the Flash left !
2 - Its a shame so many older pins are not serviced or restored, as owners don't know how to maintain them. So when a NICE game is up for sale - they fetch high prices.