Based on what I've read on Thai and Aussie forums, it's better to have the slotted egr blanking plate. I'm not too keen on using aluminum plates and removing the egr pipe. Aluminum can melt under hight EGTs. I don't want to risk it.
Almost all answers regarding EGR Blanking of the new shape DMax and MUX can be found here:
NEW D-MAX /MUX /COLORADO FORUM •
It's a long, 17-page read.
We should thank *ikloyputograpi for summarizing it for us.
This confirms my observation after blanking about the EGR being fully open at idle vs before where it was just partially open at idle. ECU thinks that it needs to open fully the EGR valve because of the low volume of air coming from the exhaust port. Once I step on the throttle even at partial, the EGR fully closes. Before blanking, the EGR is always partially open all the time except only when WOT/Floored. Keeping the exhaust gases from mixing with the fresh intake air is important for a cleaner, sludge free intake manifold, intercooler, and turbo.
I'm not saying this is gospel truth. The Australians have more experience than me, so I trust what they are doing.
So far, I haven't seen my mu-x smoke anymore under heavy load. Before having it blanked, I usually get a puff of smoke whenever I start moving and floor it on first gear.