Defense/Magic Defense: Much hHigher with lower level gear

[LuSnow]

Hello All

Me again, with a new question because I couldn't find a clear answer up to now.

I'm a level 55 summoner. For now, my body gear is a robe level 47 (woolen cowl HQ), that have 75 defense and 132 magic defense.
I'm looking for higher level body gear for now but encounter the following problem: Higher level gear body, like for example the Augmented Ironworks robe, has much lower Defense (-28) and Magic Defense (-48)! The delta is enormous.

So now I'm not sure what to do: do I keep my current level 47 robe for its high def/mag.def. or do I change for a higher level robe, meaning a crash down of my def./mag.def.?

Side note: I accidentally posted before it was complete. Sorry for that. Had to edit to complete.