RE: New XPS 15, 9530 WIFI issues.....
Most users are not reporting wifi issues with this model. The last version of the XPS 15 had a known issue with wifi but so far there hasn't been a consistent pattern of poor performance with the 9530.
That being said, some people have had issues. They have had luck with two potential solutions:
1) update to the latest wifi drivers off the intel website, NOT the dell support drivers. Some people who have had wifi issues with this laptop have had success once they updated the driver. The driver on the intel website is a newer build and may alleviate some of your problems. (note: a dell tech will never tell you to do this, but like I said, it has worked for some.) The newest driver build is version 16.6
2) this isn't a convenient answer, but your router may have a compatibility issue with this intel ac card. For some reason, some wifi devices can get finicky when it comes to how well they work. For instance, most of your devices (tablets, phones, older computers, etc.) may work fine with your current router, but something about the new system (usually a driver issue) causes problems. One way to test this is to take your laptop to a public place with wifi (if you haven't already) and try it out to determine if you're having the same issue. If the problem goes away, there's a chance that you may need to upgrade or change your wireless router. Inconvenient, but may solve your issue.
If nothing works, hopefully the card replacement will do the trick. It's overall a great laptop and I wish you luck with your issue.