The DV-60's are holding their value better because they are newer than the UX-3's, even the UX-3 SE's. The DV-60's have the more up to date video circuitry, including upscaling to 1080p and HDMI outputs, which the UX-3's do not have. Though the UX-3 does have a DVI output, it's not 1080p.
FWIW, I've also owned a Esoteric DV-50S, and the DV-60's video performance is much better.
FWIW, I've also owned a Esoteric DV-50S, and the DV-60's video performance is much better.