I am running the DANA nodular iron diff covers and am happy with them. Pretty much is a whatever floats your boat on diff covers out there. Dana, Yukon Gear, Teraflex, Rancho, ARB and a slew of others have come online offering covers for the Dana Advantek style axles.
Banks did a big study on diff covers. Changing the cover actually can have effects on things like fuel mileage, proper heat dissipation, etc. I believe you can find these videos on YouTube. For this reason I went with the Dana covers as I believed they would better take into account these types of considerations vs some of the other 3rd party offerings.
Thanks guys. I ended up ordering these JL Yukon covers on Amazon. The serial numbers matched up for the JT based on the other websites fitment for the Dana 44 front and rear.
I am using Metalcloak diff covers and skids. Price is right, and I had the the diff covers powder coated to match my color scheme. Skids already come in gold to avoid rust. Mine have been bashed into boulders and are bullet proof so far.