After getting some extensive time on Iron Maiden and being able to see some 20? plus units at MGC I have some more thoughts I can share.
Some may be useful for future owners on things to look for and tweak when setting up.
Lots of cabinet issues on the ones that were at MGC. Be sure to check you bottom panel for putty and "fixed" issues. Looks like they cut bottom panels too large and had to pound them in and then putty to fix screw ups. First one I opened had gobs of tan wood putty all over and actually holding in the bottom panel. I was told to grab another game thankfully. That one also had some minor issue with bottom panel and a few others I saw when opening were the same story.
I suggest buying inside leg brackets and outside corner brackets as you will want to swamp out the junk Stern is using. Saw 2 games with legs stripped out and ready to snap by the end of MGC since they are using the crappy inside bracket and plastic leg protectors.
I suggest buying these
Check your playfield for sunken inserts and ink smudges under clear. 3?/30 had issues at MGC. One game had lots of sunken inserts. One game had really fuzzy ink and smudges (like it was cleared before the black line was dry)
Buy a higher tension shooter spring as they come with green which is not strong enough to make the pull orbit plunge so players will start smacking the knob on route.
Ball times are VERY VERY long. Even set up hard, players will have longer ball times. Default is 20 sec ball saver for most multiballs and add-a-balls. I suggest stepping this down to 5-8 seconds at most since this is a multiball heavy game.
With 500 plays at MGC ball times were very long even with the game set up tough from the clock chaos tournament. Over 4 min average.
Game shoots amazingly well, art is great, music and theme are very 'meh' for me personally, but the code is really fun out of the box (code will need refinement to bring down defaults for ball time and leveling scoring but that will come as more people play and find the exploits over time.