I have been buying electronics items mostly rebates and some are from rebatesHQ and some are from 4myrebate.com From what I see I think RebatesHQ is better than 4myrebate.com
RebatesHQ processed rebate faster in term of validation process. If I send in a rebate to RebatesHQ, and when they receive it, they open the envelope and validate right away and indicate or update on the website tracking status whether you qualified or not, or whether your rebate is valid or not.
As for 4myrebate.com, it seems like they have a long process, they received the rebate and scanned it, and update on website status, then weeks later they validated it whether we qualified or valid or not, and again update the website. So as you can see, it takes a little bit longer than rebatesHQ
As for re-submission, both service have good customer respond, and they will honor re-submission, but probably a one chance though, after that I don’t know if they will spend time to help you fix the error, but again those errors caused by you not them, and it’s already on the term of service indicated that you must submit all information correctly otherwise you will not qualified for rebate so it’s you not them not honoring you the rebate if you cannot proof you did it correctly!