I've uploaded them to Deviant as pngs because as near as I can tell, pngs are the highest-quality file-type I can save as. The sprays themselves are made primarily for VTF Edit, as by using VTF Edit, you can negate the texture-quality set by all users one the server. This way, it will show up as a high-quality texture, even if you have textures set to minimum like I do. I downloaded the program from here: [link]
I used the VYF Edit guide section on this page: [link] When I first started. Everything on thier VTF Edit guide should work fine, as all the sprays I make are made to those specifications.
If you have any questions, feel free to send them too me, and I'll answer them as quick as I can