I am extremely happy with my G2 Diff Covers on both my H3's. My Alpha has the standard HD aluminum diff guard with fill/level/drain holes, and the second G2 cover is the brute series which is black with polished fins (the brute goes for 200.00-250.00, but the quality is extremely top notch and I got it used for 20.00!!!!!). I'd honestly pay 200.00 for it though after looking at it and seeing the quality. I ran ARB Diff Guards on my 05 Rubicon, and the quality wasn't as good as the G2. Just make sure if you get the G2 to get the proper metric bolts. Mine came with the wrong thread bolts, but a quick run to the hardware store solved that!
On my 05 LJ I went with the G2 standard HD Diff Cover (same as on my Alpha) and I really put em to the test. Worst damage was a small scratch and nothing more. You can get the standard G2 bare aluminum guard on Ebay for around 120.00. It also comes in black if you prefer, but I personally like the bare aluminum model.
The Diff Guards are fine, but you're still not fully covered if something decides to try and poke thru it (learned that on my 05 Rubicon before the ARB Diff Covers). I myself prefer a full replacement to a guard. On our H3's we already have fill/drain plugs so thats not really a new feature (on most non D44 Jeep axles that is a huge deal though), but the extra protection and cooling from the aluminum cover are features that help vs the OEM pie pan diff guard. On my Alpha I was able to reuse the OEM gasket as well. G2 Brute has it's own built in gasket that I just lightly placed a small amount of RTV on as a CYA.
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