I've been using IFTTT for various tasks, and it works relatively well, but for the triggers I've been using (RSS feed updates) the update time is quite slow (up to 15 minutes of delay after the feed is updated. For high-frequency feeds, 15 minutes is a severe delay, but in my use case this is manageable, so I'm not too concerned.
For other triggers and recipes I want to create, I need to be able to respond more quickly to an event. For example, if I receive an email, I'd like IFTTT to perform an action much more quickly (within 5 minutes at most).
Ignoring any issues with IFTTT being down, how can I determine how quickly a trigger will fire? Is the time to react based on the applet (I assume some applets might have push triggers, so IFTTT will be able to respond more quickly)?