Md Zahid
Md Zahid reviewedLunacy Editor 3.0Free Windows app that opens, edits, and stores .sketch files
 RecommendedPros: 

It's on PC! Works like butter.

Cons: 

Beta. Missing some important features. (But I'm sure they will be fixed soon)

Some personal opinions: A bit laggy. Also you can not lock something horizontally/ vertically by holding SHIFT. Some expected keyboard shortcuts doesn't exist (like ctlr+L to lock). Zoom-in & out speed could be a bit faster.

Md Zahid has used this product for one day.
TODO: - Improve the speed of zoom, especially for documents with large/many bitmaps - Find some better list of shortcuts that includes Ctrl+L - Check Shift lock - I'm positive we have it; I've just checked and it's still there. Could you record a short video of the test case?
- Performance - done. It's fast to scroll, especially with effects. - Shift-drag - done. Along with many other shortcuts: https://github.com/icons8/Lunacy... TODO: Support of symbol libraries + great, great rework of symbols.