Instead of the 3-tone cammo of the S2 version, the S3 camoflauge more closely resembles that of the European version of the non-RC Panzer VI (tan base with darker brown spots). They most certainly were not the S1 version. The markings on the turret schurtzen are exactly the same as this Panzer IV profile taken from Teamski's album:

The 21c Version DOES NOT have the schurtzen on the sides of the tank and has the different cammo scheme as described above. This would potentially compliment the S1 version, as they are from the same unit.
Has anyone else seen this latest version of the RC Panzer IV?