Telerik Upload is lacking image preview and scaling options. Please add support to show a thumbnail of images before uploading and also the ability to resize images on the client. This is really important when you have people wanting to upload photos and they select big files when you only need a small image. Images can be scaled server side but much faster upload and more convenient client side.

Examples of free components that already do this:
https://www.plupload.com/
https://nodeca.github.io/pica/demo/