The iPhone home button is sometimes unresponsive. How can I fix it?
Take it to the Apple Store. Tell them exactly what is going on and that it's a real problem for you. Even if they can't recreate the problem there in store, they will replace the device. I had a similar issue with my iPad. I took it in and explained everything and even though they couldn't replicate it they replaced it. 

If anything, they will help you get a resolution. I've never gone into an Apple store with a problem only to have them tell me "Sorry, nothing we can do."