In a raid, flashpoint scenario Sniper and Marauder are pretty much equal with Marauder slightly ahead. Skill comes into factor also, if two equally skilled Marauder Sniper were to be in a raid Marauder would pull ahead.
But raid mechanics come into effect boss knockbacks tanks moving boss etc with that said and done a Sniper would almost always win. Just boss mechanics that bone Marauders in pve.
Sucks charging in getting knocked backed slowed and trying to get into melee range:mad: