After looking at the other post on fake hondata Kpro floating around, there now seem to be fake s300 around too. From hondata:
http://www.hondata.com/s300_counterfeit.html

Counterfeit S300 characteristics

Typically sold with an ECU as used on online forums for a low price.
The installation is poor, with bad soldering, missing / invalid serial numbers and missing or incorrect value components.

The counterfeits show some or all the following behaviors:

Failure to upload or datalog.
Random rev limits.
Failure to start
Corruption of ECU table data.

We do not advise driving your vehicle on a counterfeit S300 due to risk of engine damage.

How do I know if my S300 is authentic?