How will Ninja Gear work.

[Sigmakan]

A potential higher DPS than Dragoon, a better survivability than Dragoon since the Monk will parry far more than the Dragoon, more HP than the Dragoon (IIRC)...do you see where this is going ?

Higher parry rate also gives more Haymaker procs, which is the biggest single potency for Monk, except for True strike on back. Since parry can proc on AoE, it's not even a problem if you're not the main target.

I don't have the exact calculation, but some said "Approximately double the parry rate for MNK, and approximately double the parry strength for NIN".

That's a huge boost to survivability.

Once again, this is only for OUTDATED gear (2.3 and prior). This will quickly become a non-issue.

[Reynhart]

But, from my understanding the will really only share left side gear (armor) and not the accessories. So I don't really see where the "double" comes from necessarily.
Also, we don't know the stat values they will add to each piece of gear. The initial BIS set up for release could very well entail different prices for the armor side than mnk.

If you look at a full High allagan set, you gain 168 points. Natively, you have along 260 points, so the bonus is not a small part.
Since DEX and STR are the main stat, we can assume that the DEX value will be the same as the actual STR value.

Once again, this is only for OUTDATED gear (2.3 and prior). This will quickly become a non-issue.

No this is for all gear pre-2.4.
It will be a long time before i110 armor is really OUTDATED.

[Leonus]

That much I understand, but we don't know how much dex will be on each piece of gear.

The setup for bis on the armor side could be slightly different. Maybe neither class will get the full str/dex as the other?