Your Reps wil respond, if they know what's good for them.

My three representatives are John Cornyn and Kay Bailey Hutchison in the Senate and John Carter in the US House of Representatives.

Carter gets an A. His office staff is awesome and he will respond back to me in writing within two weeks. One of his letters below.
Cornyn gets a B. Office staff is OK, and he does get back in writing within a month. One of his letters below.
Hutchison gets a C-. I can count on getting a response form her 50% of the time and only 4 weeks after I received a response from her colleague, Cornyn.