Both website builders have limited disk space. But if your website is going to live and develop, you will be able to overcome those limitations by paying extra money.

Freebie domain parking is not available. You will need to pay US$99.95 per year with Yola and US$48.96 per year with Wix on the condition of purchasing a minimal premium package of services.

Backup feature is not provided by both website builders.

Yola offers unlimited bandwidth, while Wix sets a limitation of 500Мb.

If you do not like the templates offered by Yola or Wix, you can easily change them by paying for a premium package of services.
But there are some bright sides. Yola allows to create a blog for free! Though you can not allow yourself to do it with Wix.

All kinds of site catalogs, file catalogs and publishers are considered to be a luxury for those website builders. You will not be able to have them, even for money.

Photo Album, comments and various widgets are provided within a free package of services by both website builders.

Statistics of your website is available too, but there are some limitations. The developers want to earn some extra money even here.
If you have decided to build a website with Yola, you will be able to create a chat with it. But it is not quite clear to me who uses them now, when you have plenty of social networks and services for microblogging these days.

What if you want to start your own E-shop? The functional of those website builders allows you to do it within paid packages of services.
The number of the pages which you can create is unlimited. But there is no search feature at Wix. Yola uses Google search for this purpose.
You can disable Wix ads for paying extra money. Support is a paid service as well. Yola however provides free technical support and does not load your website with its advertisement.

The main difference between those websites builders is that Wix is based on flash technology completely, while  Yola uses classic HTML..
Of course, it is your choice. But keep in mind that website building technology might effect your choice and could either harden your life or make it easier in future.

Our verdict:
After looking through the websites, which (I am sure) make Yola developers proud, all we can do is feel sorry for them and wish them strength to improve the development of their website builder.
Speaking about Wix and their websites that we have looked through, it is obvious that their week functional is hidden behind their nice-looking templates. You will not be able to create anything bigger than a plain portfolio or a photo gallery with them.
Both website builders provide users with poor features that are not enough to create a good website. Expensive premium packages will force you to search for something cheaper.