seems like a odd question.. which one do YOU want to plop $4k down on? I personally wouldn't on any of these titles. but i get asking help to blow your wad.. so here is my feedback.

Xmen and Avengers IMO are crap stern titles. (its MY opinion)

ACDC and Metalica are stern learning they cant produce crap. Of those Metallica is music I like more (to hear 1000 times as I play pinball). also I think the "cookie cutter stern layout" is better on Metallica, I hate the location placement of the canon on ACDC.. also that ugly art on ACDC is ugly.

Metallica has some things that rock, in line drop targets. Snake Teeth Braces Mod.

(totally understandable, just paying troll here)

but anyone who owns that machine is going to say how awesome it is, because 1) they think it 2) they regret blowing a wad on it.

or you have people who played it and think it sucks..

so your stuck 50/50

in the end its your cash, so which one do you want to 1)think its awesome 2) stuck regretting.

just go look at what cacusian2step rated it - buy that ... thats what I do normally never go worng and if so.. always some new guy wanting to buy it off you

I totally get your point of justification for a pin.. just interjecting that at the root of it.. asking how to spend a lot of cash to people all as crazy as you for buying things that are pointless but cost a lot of cash .. you get it.. if your married you just need to convince one person it was the right purchase.. the wife.

also as mentioned .. you need to play them - to buy a new stern blind is IMO insane. sure old williams games the rating system on IPDB and Here will line up and "get you a good pin" I think any pin is good - new sterns are hit and miss however IMO, more so then "old games"