When I had my W202 C200 key replaced 2 years ago, that replacement costed me RM800-00, which is about USD250-00 (based on current exchange or about USD320-00 at that past exchange rate).
The reason it was much more expensive than conventional RM20-00 keys was because the W202 key had to be imported direct from the MB factory in Germany - and this was based on security reasons.
I had to produce proof of ownership before this application can be processed. I was verbally informed by the technician at the local dealer that Germany keeps 2 spare keys for us, and it may cost more to get further replacements. I can't seem to verify this fact.
All I know is that W202 keys cannot be duplicated - again for security reasons. So, I suppose the newer keys with laser would cost more.
What about if we loose our thumb on the keyless S-class? Do we get a replacement too?