I feel odd being the only one to reply here, but since I have used (not owned) both SMS-1 and RDES, I can give you some info.
While the end goal is the same, the configuration of the two products is very different.
SMS-1 includes a mic and you connect it to your TV. It plays a looping low frequency tone while you use the SMS remote to adjust the settings. Since it's looping, you see the results relatively quickly.
RDES is configured using a computer via a USB connection. It includes software that runs under Windows to set the EQ parameters. It does not include its own measurement mechanism, so you either use an SPL meter and the included graph paper software, or use a separate measurement tool like Room EQ Wizard.
Does ACI still sell RDES? It doesn't appear to be listed on the AV123 site anymore (they created the product). DIYCable was working on a similar product they were calling a subwoofer widget, but I don't know when it will be available.