She basically has two big handicaps throughout FSN, one being the lack of mana from Shirou on account of him barely being a mage, and the fact that she cant conserve what little she has by going into spirit form due to some special circumstances surrounding her death.

As far as wins go, most of them are in the Fate route, but only one of them is a straight fight considering that it took Archer fighting to the death, Rin basically using every last gem she had, and Shirou projecting the sword in the stone to actually finish Berserker off. Gilgamesh, she gets her scabbard back which allows her to tank his biggest hit once. Rider in the Fate route loses but Saber is practically on the verge of vanishing with how much it took out of her, and in UBW she beats Assassin by a hair.

This is all contrasted by what happens in Heavensfeel where she basically ends up under the control of he antagonist with a limitless supply of mana and quicky becomes one of the most dangerous factors in the entire route.