Aegis desperately needs the upgrade if you ask me. Not for any added effects or extra MDT, but for the shield skill+ you miss out on that you would otherwise gain from going Lv.99 -> Lv.119. Just looking at the Eminent weapons, they give combat skill+203 and are regarded as iLv.117 equipment pieces. 424 + 203 gives us an A+ skill of 627 for Lv.117.
If we assume Lv.117 mobs have 627 skill also and factoring in our 424 + 8 merits shield skill (432), and if the proposed shield skill formula is at least half-accurate:
ShieldBaseRate + (ShieldSkill - MobCombatSkill) * SkillModifier
From what I remember during my testing, the shield base rates I found were:
Aegis: 50%
Size 3: 45%
Size 4: 30%
Going off of Martel's Ochain block rate data, Ochain's base can be anywhere from 105% to 110%
The average SkillModifier seemed to be around 0.22-0.2325
50% + (432 - 627) * 0.2325
50% + (-195) * 0.2325
50% + -45.3375%
4.66%
From past tests, block rate was shown to have a floor cap of 5%. So yeah, it looks like we're jumping into Lv.117+ content with a floored 5% block rate if we're using Aegis. Ochain should calculate somewhere around 59.66% - 64.66% block rate.
Now unless I'm missing something (such as average level of equipment adding hidden skill or block rate), I believe Aegis and Ochain deserve their respective reforged trials to at least give them the skill they're so desperately lacking from the iLv jump.