So WIX Sites have been hit as slow sites during the years. We have been dealing with this as well. But today we did some hard testing on a new advanced WIX Code site and the results are amazing.
We always use Pingdom Speed Test Tool, not just because it is Swedish but because if your site do good there nobody can complain on you :)
The below screenshot is from a test on a WIX Code page with a lot of images. There are all around about 100 images and 64 of those images are from a data collection. There are big images in the header with a slider and there is code that connects to data collection and filters out posts and renders around 16 content elements for each group in that page of 16 groups. So a lot of data collection work done.
The performance is way better than their old page with less images, less data work and that page was created in WordPress with some super cache installed and also trimmed.
WIX Code rocks!