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Generally you should see significantly better transfer rates, lower pings and more consistent performance from a hardwired connection than over Wi-Fi even in idea Wi-Fi conditions. If you’re in a dense environment with multiple overlapping bands, the Ethernet advantage only grows. This is especially true if you’re using a newer 2.5Gbps Ethernet adapter like the ones from Belkin, Startech or Anker.

However, if you’re primarily using it for connecting to the Internet and not other equipment on your LAN then your Internet connectivity could be a bottleneck, particularly if it’s rated for less than 1Gbps.
 
Some are definitely better than others.
But you must do the investigations yourself to ascertain this.
Read user reviews, pay attention to anyone that mentions "Mac".
 
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