Yeah it won’t get any better anyway that’s for sure, my car was like that when I bought it so it’s possible it was driver error in the past or it’s just wear and tear the car is on 109k and 13yr old clutches and DMF are wear items at the end of the day, yes the handling is very good on the IS for the size and weight of the car it’s well setup and has good mechanical grip, I did the service myself, I paid about a tenner for the additive can’t remember how much the oil was but all in with new crush washers it was less than £50 not sure how much a garage would charge it all depends on their labour costs