I host my website on Smugmug. They have made some not so pleasant changes over the past several years and have not really added anything new in just as long. Overall, I do prefer it over other sites like Zenfolio, Squarespace or Wix. Or even Fine Art America for that matter. The nice thing about Smugmug is that it is fairly easy to use once you overcome the learning curve of how their interface works.
Smugmug also allows you to outsource the printing to some very reputable print houses. Since Smugmug handles all the order processing, it frees you up to do your own thing. The only thing is, you have to pay the top tier to be able to set your own price. That's where all the perks are, in the top tier. Discount codes, custom price lists, and a few more perks. If you feel you can make sales, then yes, Smugmug is a good choice. Like others have said, though, you have to do your own marketing. A sales site is only as good as the sales strategy behind it. No one site will guarantee you sales, no matter how clever their advertising is.
Some down sides to Smugmug fortunately aren't too many but a lot of users find them very annoying, including myself. For one, the format options for the templates are cumbersome at best and lacking variety of options. Unlike sites like Squarespace with their 'context blocks', Smugmug offers very few useful elements and even those are limited. I have resolved to using HTML and CSS blocks to force Smugmug into creating usable content blocks. Another downside is the limited types of files Smugmug can process. For example, I'd love to be able to deliver TIFF files to some of my clients. Unfortunately Smugmug doesn't allow them. Neither can they handle 360° spin rotations.