The most important thing about LinkerD is its ease of use.
I was able to set it up in minutes without any prior experience with LinkerD. It does exactly what it says on the tin - it's a transparent proxy for micro services which allows you to easily monitor and control your application from one place! There are very few downsides - the documentation could be more detailed (it's quite short), but there is a good community around who can help you out if needed. We've used LinkerD at work for monitoring our API server and we see that it has saved us so much time and effort.