Morch Moerch UP4 or DP6

I'm considering a Morch arm, but not sure which to get. Is the premium of the DP6 over the UP4 worth it? Sonically I mean.
Can't say that I've heard both, but the biggest advantage of the DP6 over the UP4 is that it is a unipivot with lateral stabilization, pseudo captured. Meaning that it doesn't rock from side to side like all unipivots do.

I do own the DP6 and am very, very happy with it. You can save a bit if you get it in chrome and not gilded gold.
I had the UP4 on a Spacedeck and was very happy. My feeling now however is that I should have sprung for the 6 because I believe it really would have been better. Not sure how I can come to that conclusion since I have never heard one, but my thoughts are distilled from everything I have heard over the years on these arms. I would add that these days I consider the 4 a poor value. This is what used to be a $1000.00 arm selling for close to $2000.00
Ptm, I also have an Audio Craft which is a unipivot and I don't like the rocking action so I agree with your point.

Harv: Yes the price has increased significantly recently, so I agree with your point.
I have done side by side comparisons of the UP-4 and the DP-6. The DP-6 does sound considerably better, but it also costs more. I really do not like the ergonomics of the UP-4, too wobble'y. If the difference was only the sound then it would be a harder choice, both offer good sound for the buck. But when the ergonomics are factored in I think the DP-6 is a much better choice. I also think the 12" armwand is well worth the extra money if your table will accommodate it.
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To close the loop, I just picked up a DP6. Hope to have it installed by next week.