I just prefer having one screen. Personally. With Laptop it depends if your running external gpu. I got an Alienware at an excellent price local store on sale. I know BizonBox can be used with Mac, and Win personally. I use Mac, Linux, and Win. So I know from experience PNY ram, and some flash drives don’t play well with mac. I worry about that happening with say an expensive GPU. I would go with Nvidia, or Evga just because they have no hassle 3 year warranty on parts and labor. Don’t buy junk, and you don’t pay twice. I once found out the most expensive car in the world is a cheap Mercedes. I’m sure I bought the car more than twice. Then there is time that costs so much. If you dedicate a hassle with not having a computer up for say 14 days because of a mail order GPU return policy. I don’t live near Fry’s anymore. 
http://www.bestbuy.com/site/evga-nvidia-geforce-gtx-1080-8gb-gddr5x-pci-express-3-0-graphics-card-black-silver/5851744.p?skuId=5851744