Optimax/super unleaded - worth using?

[church]

Picked up the Turbo R last week and on the first fill up went for regular unleaded, and now I've read the owners manuals....... it states that super unleaded should be used. So my second tank I filled with optimax and haven't really notice any difference (although with so much grunt it may not be noticable). So was wondering if anyone has had any experience of this and does in effect running/reliability in the long term?