Sexu is one of those tube websites that basically gives you access to a hell of a lot of HD porn completely free of charge in a simple, usable interface that doesn't mess around and just gives you the good stuff from the get go. It has a nice minimalist design and a few extra features that some tube sites lack that put it ahead of the competition when it comes to watching porn videos in the Internet.
You'll find that Sexu.com breaks its content down into various tags, so if you're looking for a particular type of adult entertainment, you'll be able to find it with very limited issue. This tube is also pretty much filled with professional, full-length content as well, so I'd suggest if you want amateur stuff or scenes not presented in HD, other sites are likely to be more fitting to your requirements.
There are sections on Sexu that will show you the latest scenes uploaded to the site, the most popular scenes streamed and a 'hall of fame', where the people who run the site give you their opinion on what scenes are the best.