None.
The vehicle is very comfortable.
Above 4000 rpm nice engine sound.
The turbo whistle is very motivating The turbo howling noise inside the cabin is not so good.
The sixth gear is very economic.
The engine torque is usable in every gear.
Sometimes buzzing & rattling noises are coming from the cabin when riding on uneven surfaces.
Handling and steering is very good.
I am also the (proud) owner of a Renault Megane Sport 2.0T.
It is the best and also the worst car I have owned. From a performance point of view it is absolutely brilliant and I have had various Golf GTi's and a Golf VR6 over the years so I have grounds for comparison.
Unfortunately the build quality and after sales service is some of the worst I have experienced. This car rattles and vibrates at idle, at speed and everywhere in between. Some of this was resolved after I discovered that the directional Pirelli tyres had been fitted the wrong way round on the passenger side of the car and had it rectified.
The rear view mirror has a habit of coming loose at 180 km/h and above this speed the sunroof (closed) lets in so much air that it might just as well be open.
Unfortunately, the dealership has a hands in the air attitude (it took them a year to supply me with an owners manual) and apart from taking legal action I am not getting any help from them.
I will not replace this car with a Renault and will not recommend this model to anybody (unless they like roughing it inside their cars).