UMx series typically has a signature for stage monitors, whereas the w series leans towards a more home listening experience. I don't think the UM1 is a good place to base assumptions on the UMx series considering it's a single BA compared to the three way crossover of the UM3x, but either of the westones are great, and I prefer them over the others mentioned in this thread. I also find westone as a company to be extremely satisfying with prompt responses to requests, and an excellent RMA process, but you shouldn't have to use it since their products are made to last.
Well, If I'm just listening music at home, should I consider the W series over the UM series? Big Thanks :D