I struggled for a long time before buying this camera. Hesitating in a7m3, a7r4, and a7c, The performance is similar, the a7r4’s pixel is a bit higher, but a7c is also sufficient.
The most important thing is that this camera is only 425g, easy to carry! And it looks pretty nice.
The flip screen is suitable for taking selfies and vlog shooting. The fixed focus is fast.
So I finally chose the Sony a7c.
Alex Lux 
Leo-nike 
Ken Cheng 
John Shen