I have modified the rtm on my chosen rfq format to have a big bold note asking the vendor to respond by fax, with my fax number. I have also added my telephone number and email contact. I would like to suggest some sort of a "please respond via X method" field included as part of the basic form. I would love to see the "Date Required" field changed to something like "projected delivery," or "availability," and to have the required date field (which currently cannot be left blank) dropped so that the person receiving the rfq can fill in the availability or lead time just like they can the price info. If I have a required dock date(s) for them to shoot for, I enter that as text in the body of the rfq.  
Thanks for keeping it evolving, and letting us make suggestions!
Ann Luce
EMI Filter Company