well its either true or
a really good $150 placibo, sssssssoooooo what i did was
take mine apart when i got it back from them to verify what they did and it was all as advertised. they also wire wheel the outside of the box and cleaned up any corrosion, they just didn't do the circuit board but the shell was done too, an extra step that meant a lot to me. well worth it in my opinion.
and when i installed the ecm, the codes it kept throwing were no longer being thrown, so hopefully it will cure a lot of your issues. the only one i kept having issues with was my egr, but now i know it wasn't the ecm, and now you will know, if you still have codes thrown, its the sensors and not a funky erratic ecm.