Hi there!
I think the answer might depend quite a lot on what you’re exactly aiming for.
The EyeX is a device we especially developed toward the consumer market as well as developers. Meaning, we can provide it for 99$. This doesn’t mean at all it’s worth, depending on the usage it performs even better than e.g. the Tobii Rex, however under other circumstances the Rex performs better.
What are you trying to achieve, integration into an app/game or something different?
Cheers,
Konstantin