S9- I think the stuff you got ain't gonna do harm, if any at all, to the car. Exhaust, filter, BOVs are pretty standard stuff. If you are worried, then I think you will need a boost controller more than anything. I think its the unstable boost and boost spikes is the thing that causes ZZs turbo failure and moreover, his car is standard!!. I think the worst harm you could to your to your car if you are crusing at high speeds constantly is to do so without a boost controller. You need to stabilise the boost in order to protect or prolong the life of the turbo. Or, it could be that something went into the turbo which caused the fins to breakdown. Installing a catback will improve the exhaust flow and reduce back pressure which will give rise to increase power. Once you start improving the performance you will need to consider controlling your boost to ensure that you don't naturally overboost (due to improved performance). I am seeing boost spikes at 1.7bar on my car which I think is dangerously high. Fortunately I don't get to travel at high boost and high speeds for a prolonged time so, I think I am still safe. Anyway, as a safety measure, I will be installing a boost controller soon to ensure that I don't f-up my turbo. Anyway, in short, I don't think you have anything to worry abt with your mods. Anyway, I don't think there is anything that will be covered by guarantee by your car dealer. They will prpbably say its wear and tear or find some obscure reason to avoid warranty.. only my opinion....