ABS module repair

I have a bad abs module on my 99 GMC seirra. 2500 4x4. I have seen some rebuild services on ebay. They claim they can reprogram the module to a better than factory new for a cost of 129. plus two way shipping. I am wondering if there is anything to there claim. Has anyone ever done this? I know it is a 600 + repair for a new module.

Here are some others that repair ABS Modules:

http://www.absfixer.com/
http://www.modulemaster.com/en/index.php

//2000CAYukon

Thanks for the help. I believe the module master in Moscow Idaho. Is the one offering the repair listed on ebay.