Some of these restorations look great. I wonder if arcade guys look at pinheads the same way "wow, that pinball looks great!"

I remember sit-down sinistars (awesome bass), NEVER knew a sit-down roadblasters existed. Always played the standup.

I think emulation can lose it's appeal by each one of these:
1. You're running a pi box with home game controllers not arcade controls like a real joystick, trackball, spinner (that's me right now)
2. It's not in a real cabinet but using your TV as the monitor (that's me right now)
3. Whatever menu interface frontend you chose isn't user friendly (I'm running retropie which is nice)
4. You have WAY too many dam games loaded. So many you get overwhelmed and give up (this is also me because I downloaded a pre-made image file).

I think if you did it right and maybe dedicated one cabinet to each:
1. driving games
2. fighting games
3. retro games with less than 3 buttons (donkey kong, pac-man)
4. trackball games (missle command, crystal castles, marble madness)
5. spinner games (tempest, arkanoid, tron)

you would be in good shape. I don't need to play on real hardware because the frame rate is truer. I don't need the real shaped cabinet it was in originally, I don't need to see the marquee for that game (though I have seen videos where the marquee was an LCD that changed with game selection):

60-in-1 are typically remakes (IE they reprogrammed it from scratch), so yes it's not an exact copy. Probably also how they legally get away with selling those boards without the companies coming after them (MAME is a grey area, and a company selling cabinets in california busted for it).

Mame is running the original roms that were extracted from the boards. So the graphics, sounds, and code are identical. But because they are running a simulation of the original CPU, there is usually a minor difference in speed (hence above saying how double dragon no longer slows down or has sprite flicker). Double dragon (and golden axe and altered beast for that matter) was pushing the limits of the CPU at the time. Most people don't care, or can even notice. If you're trying to set a world record for a classic game, they only allow it to be played on original hardware so it's a level playing ground.

Here's the other thing with Emulated games. So long as you aren't playing 3d games, you don't need a giant desktop tower sitting inside your cabinet (even though older desktops are dirt cheap or free). The raspberry pi3 is barely bigger than your palm, and runs on less than 12watts. Get yourself an efficient LED monitor that uses 25 watts and you have a rig that uses less power than a lightbulb (and won't heat up your gameroom).

On that note, there are pi clones like the ODROID that feature better CPU's and video to run early 3d games:

Couldn't one cabinet with a steering wheel, gas/brake pedal, and hi/low shifter pretty much cover these 3 games? Of course I don't know the logistics of getting variable gas/brake pedals working in MAME.

PACMAN you are the HEP of arcade restores, absolutely gorgeous.

One of my favorite games as a teen. Loved it so much I bought it on the atari lynx portable. Thankfully my local arcade has this title.

"harumph harra harra harr harrr... nice work!"