You'd probably see small improvements with a service, terraclean is done via fuelling! I never had mine on a rolling road but a mate of mines done a before and after on the same dyno and it made an extra 10bhp after the terraclean
Can anyone tell me if the toyosport one will fit the 200? I know the eBay ad says 197 but couldn't tell you if the manifolds are the same? One of the flexis blew and it sounds like a harley Davidson so it's time for a new mani haha