Ping Issues using Thunderbolt to CAT
So I did the test using the ping command in terminal

For Google.com

Ping Google.com


The result for 2.5 GHz WiFi was: 


  20 packets transmitted, 19 packets received, 5.0% packet loss
  round-trip min/avg/max/stddev = 16.295/18.872/30.858/2.935 ms


with transmit rate of 130.

And for my 5 GHz WiFi:

15 packets transmitted, 15 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 17.451/19.066/21.444/1.157 ms

with transmit rate of 216.