I have both cubes. I got the POM last week. I don't like it! I cannot say I'm disapointed, because I wasn't expecting anything specatcular...I bought it more as a curiosity.
The POM is heavier, 1mm smaller - maybe 0.5mm (nobody mentioned about this until now) and is very noisy. It has a A V-ish feel, due to the harder plastic I guess and might resist better in the long run; maybe not get sticky over time as the normal GuHong.
Having this aspects mentioned, I think the POM version is worse than the normal one. Mine's jams and locks up sometimes (maybe it's just a bad version..but I don't think so, cause I set it up, lubed and did everything necessary). The difference in solving times is irrelevant, obviously, but what makes me choose the normal GuHong is that when I switch back to it, after doing like 30-40 solves with the POM, the classic one is a charm and feels much better in the hands.
I think DaYan wanted to avoid the sticky feel of the normal GuHong (in the long run) and came up with a different plastic, heavier and harder, but the experiment is not that successful in my opinion for the GuHong.