I have a bunch of microfiber long sleeve shirts that I often wear under a sweater. They are comfortable but snag easily and are wearing out. Their other big negative is they retain odor. I think the Merino long sleeve top works better. More comfortable, gives more warmth and doesn't stink up. My  gripe is that $50-70 is pretty steep for what is essentially a long sleeve t-shirt. However, I've not been able to find anyone else making these items in Merino wool, so I will likely buy more over time.