Amazing Princess Sarah is a well made platformer with a pretty good difficulty curve. Sarah fights enemies the Super Mario Bros. 2 way: you mainly kill your enemies by picking up items -- or already slain enemies -- and throwing them at your foes. If you time it well, you can get cascade reactions where you kill multiple foes with a single throw.
The (forgettable) story is told without words through simple cutscenes. The same style is used to introduce the bosses.
Where Sarah is frustrating, is in the level design. Even for a game in the platformer genre, there is a LOT of backtracking here as you mainly fight your way to a switch, flip it, then backtrack to a previously locked wall/passage and continue.
Enemies respawn throughout so you are always in danger, luckily save points occur frequent and are mostly well placed so you don't have to repeat particularly difficult sections too often.
Most annoyingly, flying enemies and enemy projectiles go through walls, and as you'll be spending a lot of time passing through narrow corridors next to other sections you've either already visited or will visit next, there are a lot of cheap hits as a result. Luckily there are also sections where you can just dodge or kill enemies without worrying about cheap hits too much.
Overall the experience is a good one. A well made game and worth the (low) price.