Now that he's bought a good Canon camera for his son, what is a good laptop to edit video? He's looking at the 15" MacBook Pro or the Dell XPS 15. Leo says both are excellent and it really comes down to what OS he'll want. Leo says that if he's been using OS X, then getting the Mac is the way to go.
Leo also says he can edit video on Blackmagic DaVinci Resolve 12, which is free. Final Cut Pro is $200, and iMovie is free. Mac vs. PC really makes no difference now, though.
Mark says he's shooting in 4K. Leo says that will be hard to do on a laptop because it's very taxing on resources. So he'll likely need to go with the Dell and max out his RAM to 32GB for that. Apple has been slow to update their processors, actually. Processor speed is the #1 issue for 4K video. And for that, the 5K iMac may be the ideal option, but it's not portable. One option is to create an edit list using lower resolution proxies and then move that over to the 4K footage.
He also says that he can get the Dell XPS15 for $700 less at the Microsoft store. It won't come with any Dell support, but Leo says go for it! Microsoft will then support it and it's probably superior than phone support with Dell. The PC will give him more bang for the buck.