One is rushing to leave, but just a bit about the eye thing.
You must satisfy yourself about taking anything and flying. Only published data and the law can be the guide. Having said this, there is the old argument about flying after a perfectly useless night trying to sleep. I have never felt so fresh on earlies as when I used this.
This is quite without qualification, but sometimes I feel that eyesight is fine-tuned by other muscles. Extra-ocular for example. Of this I'm near to sure.
When such muscles relax totally, the whole fine-tuning goes out of kilter and almost has to be relearned. I have often noticed that an extremely good rest leaves me with poorer focus for a while.
Just a thought, though what I didn't say is that I uses much, much less than the recommended dose, sometimes breaking half a tablet into small bits and leaving them beside the water. If I wake, I take another fragment.
There are CR tablets. Ambien I think. DO NOT use these and fly...they really do spread the drug over a long period.