I think they are definitely made for Comply tips --- they have a clear effect on the sharpness of the peaks, making them a lot more listenable, and allow for the treble extension not to be masked by the last treble peak (which is also, in my estimation, the root cause for the perception of "harshness" in the treble, as it makes cymbal clashes and other similar sounds a bit splashy); while the Tx tips do the best job of smoothing out the treble, I find that it starts to encroach on transparency, so I still recommend the Ts-500, as it's more comfortable, mostly maintains the overall signature, and still manages those peaks.
I've managed to get used to them with silicone tips but as I mentioned, I tend to listen at low volumes. The effect of tips will have different effects on different people; I've managed to find that dual flange wide-mouthed tips do a good job taming treble for me, but it might not work on others. I don't like using the spacer rings, but they absolutely do have an effect on where the quarter-wave resonances crop up in the treble; this effect is clearly shown in AKG's
studies regarding front volume differences. Keep in mind that this "predictable" effect within an ear simulator doesn't necessarily coincide with real world perception, as ear canal shape, curvature figure into differences, as well as a person's own perceptual inclinations to sibilance and harshness.
Also wondering if James has tried the effect of K3003 tips on the 2000J; even though the two types of tips are similar, when the K3003's tips affixed to the 2000J, they do make the treble a little more gentle and less harsh by just a tad to my ears --- more like the K3003 in nature. The added brightness ends up coming from the psychoacoustic effect of a tighter mid-bass response, mostly. From the beginning, I've been a little baffled by their choice of silicone tips; perhaps it's that these tips help bring out midrange detail a little better, but they do tend to make the treble quite a bit less palatable.