I have been a dell customer for many many years (laptop + desktop). I bought a Dell XPS 15 9550. These laptops were poorly designed by Dell and included a defective battery (along with poor engineering around it) that with use the battery would swell up so much that it would push the track up up and out of position by as much as 1/2". My trackpad no longer works and the battery represents a serious fire hazard. 

I spent hours dealing with customer service and Dell has done absolutely nothing to help address the issue. Absolutely no accountability from Dell. If you look up online, this is a very common issue with these laptops and everyone has had a similar experience when dealing with customer service.

Something goes wrong you better pray the warranty is still available (even if Dell has sold you a defective product). The people who paid to get their laptops fixed by Dell got the same defective battery installed, which later blew up once again.