The last time i heard about the GTRS4 wide body kit for the BMW M4, Vorsteiner was presenting to us some pictures mid development, and they held a lot of promise.
Now that the kit is finally out, I can say that the modifications really held up to expectations.
The kit from Vorsteiner is not as oulandish like some products from Liberty Walk, but when it comes to looks, it seems they were spot on with the design. More so, if you actually think the GTRS4 kit is not enough for your BMW M4, there are a lot of complementing parts you can also order from Vorsteiner, like a quad exhaust tip or various other interior trims.
While the visual improvement is the main reason for buying a wide body kit, the GTRS4 does you one better. It seems that Vorsteiner was hard at work to not just keep performance intact, but actually improve on it. The overall drag coefficient of the car is reduced, and the airflow is made to work for you, like providing extra cooling for brakes. All in all, this kit for the BMW M4 is something worth the wait, and I believe it will be a while until something comes out that stands on par with it.