Bellagio:
Haven't been to Vegas in a year
but usually watch Bravo decently.
Last I knew games were the same except 9/18 replaced 10/20, played with $3 chips. But that game is the least likely to go. In order of availability I would say: 20/40, 4/8, 40/80, 9/18. But during peak times, 20/40, 40/80, then a toss up between 4/8 and 9/18. The 4/8 seems to usually only have a table, while during peak times there can be 2-4 of each of the 20/40 and 40/80 games.
But my best advise is a few weeks out to start watching bravopokerlive on the same days of the week you plan on going to get a very good feel of what is likely to happen.