I've been using Eto for a few years. It's amazing toolkit.

If anyone is working on cross-platform desktop app in C# which is meant to look "native" on each platform, then Eto is the best toolkit there is.

Yep, I agree - Eto is great for native controls! I consider Eto and Avalonia to complement each other rather than as competitors.

i tried using eto for a personal project, but i had to abandon it because i ran into a problem that i couldn't solve myself, and which got zero responses on the forum :(

https://groups.google.com/forum/#!topic/eto-forms/8tivDpoC3I...