I had the LX-20, not sure how the LX-25 compares but it's a decent tire, doesn't have all of the bump compliance the Defender does. That does translate into that last few percentage points in terms of comfort.
I'm currently on a set of Defender LTX at 74K just above the wear bars, and if I didn't have an alignment issue there's no doubt I could have reached 80K with easy driving.
I will be replacing these with another pair of Defender LTX.
That being said, in terms of highway comfort, the reigning champ IMO is the Latitude Tour, NOT THE HP, but the standard Latitude Tour. The Defender I feel is still the better overall tire, the Latitude Tour doesn't extract the water as well as the Defender and the Latitude gave me a few white-knuckle moments in moderate rain at 65 MPH.
In terms of road noise, I would give the Latitude a 9.5 and the Defender LTX a 9.3. Both are extremely quiet, but the Latitude is a glider in the air for a rough analogy. If you have driven on a pair you know what I mean. You cannot trust the reviews as I see the same reviews on the HP version so it's a crap shoot, the HP is a different animal and stiffer.
The Defender lasts longer, more confident in the rain, and is extremely smooth and quiet