Mori!
I know you are the best Guard ever existed in the game. 
Just joking.
But…!
Ask Hayde(DT), Evito(DT), CK(Tos, Necro, Conq), Pusjo(was one of the Guard on Mithrelle, he is not playing anymore), and the guild leader(on Guard, I do not remember his name) of Fail Bunch back in 2014 or so I think, and a couple of other players that I do not remember their names. Behind them there were dps’ers like Nialcara(on Demo), Chevrette(on Pom), and a bunch of other very good players, who pushed very hard from the very first second!
So ask them how garbage was the aggro in T3 Guard armor set against Hayde’s, Evito’s T4 tali DT on Mithrelle, on Strom, on Emperor…
If you want to prove your skills, ask them, not me!
For the end words:
In my humble opinion, T3 Guard armor set is not worth for 5 minutes to keep it in the current game with the current geared player base, if you have better/higher gear, change it.
(T4-T5-T6 geared players will be around you most of the time, with legendary rings(gems), legendary cloaks, arena necklaces, with a tons of dps and crit. Without minus hate of course. 
)
Only keep it, when you want to watch the game and travel with the raid.