Thanks for your feedback and thoughtful question. You're absolutely correct that a simulation of a game can never be as accurate as an emulation since a simulation is based on observations of playing the game rather than running the original code, although every effort is made to make these simulations play as closely as possible to the original handhelds. Studying the instructions that came with a game helps since there is often a lot of detailed information about the gameplay, scoring and fail conditions that help to ensure accuracy. And where contributors own the original handhelds, they help to playtest the simulations to ensure it feels and plays as close as possible to the original.
The purpose of this collection is to help recreate the experience of playing these vintage electronic games so they can be preserved beyond their physical lifespan while still respecting the copyright of the original manufacturers by not making use of their actual source code in these recreations.
Thanks again for playing and for your feedback!