{jcomments off}In short, with the 7th ed. rules, snipers seems to be a less favorized choice for Tau, although I'm not sure it's wise, seen from a wider perspective. Just forget the vehicles...

New codexes that comes out normally contain one or several new high-toughness, multiple-wounds units which gives the sniper drone teams plenty of non-vehicle objectives to shoot at.

Characters and independent characters no longer have precision shoots, the drone team is now the only troop choice that by default can pin-point out certain enemy models, which can be useful in most games.

Having an etheral nearby makes the sniper drone team more reliable when pin-pointing away certain units/models within 24". The units will also be incredibly lethal if put right behind the frontline of fire warriors. The Supporting fire consists of a few markerlights (if lucky, severlily boosting the fire warriors) and almost for sure x3 sniper shoots on charging units where each hit can be put on the most dangerous CC character (if lucky, even AP2).