| I have the Sigma mods done that you are talking about. The standard gearing for a 996 is 15/36. I changed to 14/36 and ran it like that for a while and have just changed to 14/39.
I haven't ridden it much since then but it goes a bit harder and the front lifts a bit easier - I reckon the mod is well worth it. I know someone considering going to 14/41! | 
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