Justin Timberlake has a really nice website, he has a one page website, and i think its nice because it sends you to the certain place of the website. The only page that is seperate is the shop, which is normal. I think the color pallete and the theme goes well with what Justin represents and thats Tennessee. He actually lives in Tennessee and he brought that to the website.
Now Justin Bieber's website is also like a one page website, it send you to a different link, but is on the same page, it doesn't create a different page, also its very generic website, it sends you to a different page when you click on shop. Lastly i think that its an good overall website.