Printed off the 2 ducts and have them mounted with 2x Ultra Kaze's. Here's a comparison:

Old setup
Kaze Pull + Stock push + no ducts = ~53°

New setup
Kaze Pull + Kaze push + 2 ducts = 63° / 59° (there's a few degrees difference between both boards strangely..)

Are the above temps expected with my new setup? I was expecting a bit cooler, especially in this air conditioned environment.

It's possibly worth noting I don't have top or bottom plates due to printing difficulties.

Edit: temps have risen to 65° / 61° now