most recent post about MGM in the upgrade thread in the Vegas forum.

Biggest issue, what days of the week. Midweek is always a better chance for an upgrade. But, if you are staying mid-week; and this is your honeymoon --- I really question why you just don't drop the coin on the upgrade, and then NOT have to worry (or potentially) get an even better upgrade.

IMHO, these suites are really not that expensive to buy into.

I also agree, MGM is not considered a luxury property; though their suites are a very good value. (and MGM has a lot of awesome dining options, including one of my favorites Shibuya Japanese Restaurant)