I love this layer. I switched to a shell jacket with no insulation this year and bought this to test out as my second layer (over just a long sleeve t-shirt). Even though it is heavier weight than other merino wool baselayers it still is relatively light, fairly thin, but feels cozy and sturdy. It layers easily over another layer, and under another layer if needed. It doesn't bunch up or feel too bulky and it keeps me nice an toasty. Just for reference, with my shell, this layer plus a t-shirt I'm warm enough for ~25°+ days. For colder than that, I throw on one more layer.
My only wish is that it had thumb-hole cuffs like the crew neck version. I didn't realize that it didn't until it arrived (my mistake)