I really wonder if the overall success or failure rate (depending upon whether the glass is half-full or half-empty) is much different than AW+AM marriages.
I say no it isn't much different. I'd say the stats probably tell a different story but realistically, the stats for AM/RW are a much smaller sample size and intercultural unions are much more difficult to sustain over a longer period of time. I've never been one to pay much attention to stats. But, once the positives become "old hat" and the negatives become much more prevalent, maintaining a marriage is much more challenging in any marriage and intercultural, much more so.
Perhaps due to being naive, when I got married I never considered divorce as much of a possibility. After nearly 10 years, unfortunately it became reality. Now I find myself at times borderline paranoid, which puts a helluva damper on things during those times, that's for certain.
Few people enter into a marriage with the idea that it will fail. My first marriage lasted 11 years and right up to and after I filed for divorce, I thought it would survive. I think I was more afraid and embarrassed of the failure more than anything else. That paranoia is a natural reaction and a probably healthy virtue that helps to strengthen ones resolve when they find their next partner. Those that do not experience those feelings, might be in for trouble in future relationships. Of course this is only my opinion and guesstimate.
In the end, do statistics matter?
After all, it's going to come down to the two people involved, and in part the situation that they find themselves in (or in other words, what unexpected life challenges that they must face together).
IMHO, no, none of them do. At the end of the day it comes down to the two people in the relationship and how strong they are in their feelings for each other and remember, it takes two. No matter how strong, in love or committed one is, they are still only half or 50% of the relationship. Not just this particular pursuit but any man/woman relationship, if you feel you are much more than half of the relationship on an emotional level, you probably are and should think much more seriously about your potential partner