For me it's my BOP 2.0. I played the original back in the day . It was my first pinball machine I purchased to start my collection . Since then she's gotten new everything. Playfield, ramps , plastics,blah blah blah . Had to have the DP 2.0 kit and recently she got transplanted into a virtuapin cabniet. So yeah , lots of money into it but It just doesn't matter to me. She's never leaving!