I love seeing these get attention here. I've been really into them for quite a while now. A big part of it for me is that the cabs have authentic artwork on them. I was never aiming to pick up The Simpsons, but I'd def buy it if I saw it for $200. I don't have the time to go hunt for it though.
I've really gotten into modding these as well. I've kept the games/pcb's stock. I'm more into making the cabinets as cool as they can be. I have a whole list of things I want to do (larger screens, light up coin doors, better joysticks and buttons, higher quality marquees etc...) to all of my cabs once I have the time.
Here's a pic of three of my cabs:
The control decks on the SFII and MKII are not stock and I've improved the kickplate art. All three machines have IL sticks and buttons with cherry microswitches. I think I've gotten more enjoyment out of modding these things than playing them! But as someone who grew up playing these machines in the arcades its super cool to own these and I enjoy improving them.