Considering their performance against Sidious, I'd give this to Maul and Opress. SO got taken out rather quickly, and while Maul did only slight better, even hanging with Sheev for a short while should put the duo above the Pratorean guards.
Maul was capable of beating Kenobi several times in the Clone Wars, fought for a fair amount of time against Sidious and was shown to have strength in the Force comparable to Dooku in the Son of Dathomir comic. He probably solos the guards, with Savage just certifying the victory.