It's basically a tanking set, it's just been outclassed by later sets. Particularly, for STFs, the MACO shield alone gives similar resistance out of the box than the Aegis set bonus gives when it's fully ramped up.
Anyway, right now, though? Might actually be a worthwhile project. With the tribble test weekend being over, it looks like S7 will launch this week or next week at the latest, not leaving you much time to get another set before they become locked on the other side of the reputation grind.
Basicly the Aegis set is a shield tank set with a hull tanking proc, that is useful on ships that fight on the move. I have fleetmates who do elite STFs with the Aegis and do just fine.
I will say that the Borg and MACO sets are fairly easy to get and (maybe even in S7) cheaper than the Aegis.
If you have the ECs you can buy the complete sets on the exchange which is cheaper than buying the materials on the exchange. If you are buying it for Dilithium (via unreplicatable materials) it's ridiculously expensive (something like 50K+ Dilithium).
My Romulan Liberated Borg character made it to Level 30 and beat the (old) Defense of New Romulus with the skill point bug.
i think the aegis set is pretty easy to craft. it will just cost you some dilithium for uncommon material.
i have moved it around trying it on various ships. it found a home on the atrox and seems to do pretty well on that ship.
with the nerf coming in season 7 on the borg/maco set up i crafted one more which is currently in the bank, just in case. most of my ships run borg or maco 12 now.
i do have the dreaded fully upgraded reman set and i use it, but i would not recommend going through the hell to get it. it seems like few know how to run the vault and honestly the set is just not that great imho.
i like the aegis set and i think the skin is great.
The Aegis set is the only end-game set you can purchase at the Exchange.
It was generally regarded as the weakest of the VA sets and an easy to acquire prerequisite before doing STFs.
Not sure how it compares, now.
"Don't let them promote you. Don't let them transfer you. Don't let them do anything that takes you off the bridge of that ship, because while you're there... you can make a difference." - James T. Kirk