*sigh* no it isn't.
THAT above is Tier 3. Notice the color and lack of giant blades coming out of the shoulders.
That above is the 10 man Tier 7 version. It does resemble tier 3 but it's a rather ugly color and the chestpiece is totally different than Tier 3 was.
That above is the 25 man Tier 7 version. It's looks the least like tier 7. It has weird giant blades coming out of the shoulders which the original tier 3 did not and neither did the 10 man version. It also has a different chestpiece than Tier 3 AND 10 man Tier 7. Which really doesn't make much sense.
So yes Tier 7 does resemble tier 3, but it is not the same thing. I just wanted to point this out because people are often confused and do think they are the same sets.
Like me for example I LOVED Tier 3, but I can't stand how Tier 7 25 man looks. The 10 man version is okay and would be great if it was the same color as T3 was, but alas...