Two questions on setting quotas

>If i don't check the "drop" box when setting quota policies, then what happens to the request? Is there a default message, or does it just fail quietly?

By default the system would enforce rate limit at 50K messages/hour for an api.
we return a HTTP return code for 403 with the following message
"You have exceeded your Global Quota of 50000 request/hour"

>Also, if there is no user-set quota, and you hit the Apigee limit, do you get an email?

Unless the user specifies a rate limit of his own he does not get an email as of today.

as mentioned above we enforce the limitts for an hour and the hour starts from the time you start sending a message and it looks like you split the hour therefore you did not end up getting rate limited by us.