Seems like a pretty easy thing to test there brother.
Personally I found the 2 set bonus for Destro to be worth roughly 2-3 average ilevel, it's a pretty good bonus. I would recommend you spend 5 minutes on a Dummy with both sets of legs equipped, and just see how you go. I suspect it won't be worth it.
I compared 483 gloves (2 set) to 522 gloves (no 2 set) and found it was pretty DPS neutral, but gloves don't add as much as legs.
Originally Posted by TheSerialSniper
Shields need to be reworked to absorb a % of incoming damage up to the limit of the shield - Instead of absorbing all the damage at once.