Nearly all of the EM's in my stable are 5-ball replays. Not coincidentally, nearly all have the same game length.
This is a good thing, because when people visit my collection, everyone can take turns more or less equally. This is especially true when the games are on location (say, at a museum or convention) so that others aren't kept waiting too long to play.
Replays are fun because that *snap* means you are doing *extra well* (and announces it to others). That knocker isn't just "par for the course"... only the *good* players get them. So I set my replay thresholds at somewhat difficult intervals in order to egg the player on and get others involved. It makes everyone want to get their games knocking too and join "the pros"!
Among them, I do have one AAB game (Flipper Fair) but it, too, has about the same game length as the replays because of the steep difficulty. Again, this is a good thing, because it feels like it belongs with the others in terms of time and skill.
Based upon this perspective, you can see why I won't give "runaway AAB's" high ratings or want them in my collection. They have the potential to monopolize a player for too long. In some cases three, four, five times as long... or longer. Our last EM-tournament stalled many times due to Yukon, the only AAB, hanging up play-times for everyone else.
Now, in some rare cases, the replay version is the adaptation from the AAB-original... and many of these have the reverse problem: Too hard! Cross Town is one of these. Just doesn't make sense as a replay. The whole risk/reward thing falls apart. Besides, if you've ever played a properly leveled Subway/Flipper Fair, you know it still doesn't last long!