vSphere Replication Performance Impact

Solution 1:

If you are talking about storage replication, you should check two important things:

  1. Storage performance - in your case it shouldn't be a problem.
  2. Network performance between the servers.

Is there a performance hit from using replication that would negate the benefits of the all flash storage?

I am using StarWind VSAN and have zero issues with write performance on all flash HA config.

Solution 2:

Is there a performance hit from using replication that would negate the benefits of the all flash storage?

It depends on how much 'spare' resources you have left on your cluster after all your VM load. If there's lots of spare CPU/memory/network-bandwidth/disk-bandwith-and-IOPS then no you should see little if any impact during replication, essentially it'll work as a background task and use those spare resources to do so.

If you've not left adequate resources then the impact will be greater as the replication does take an amount of those resources away while it replicates.