The shirts I tried out were:
1.0 Baselayer (loose fit v-neck with cap sleeves)
2.0 Baselayer (Form fit v-neck short sleeve)
2.0 Baselayer (Form fit v-neck sleeveless)
3.0 Baselayer (Light compression v-neck with cap sleeves)
A few things that set these shirts apart are the fact that they are engineered without many seams. They are sized based on height/weight. XoSkin uses a combination of PTFE and copper fibers to keep you cooler, reduce friction and odor, and promote a healthy environment for the skin.
Overall these shirts have been excellent. They wick well and are comfortable in a wide variety of conditions. I'm not sure that they really smell less than other synthetics after several days of wear, but I do notice that the odor washes out unlike the permastench in my other tech shirts. Even the heavier shirt is comfortable in warm temperatures. The main thing I'd like to see is more patterns.
I didn't find there to be much compression in the compression shirt. (Maybe I need a smaller size?)
The sleeveless form fit was my favorite for all factors. I love it for running and hiking.
The hand of the 1.0 was silky and I'm not a huge fan of that type of fabric feel. Otherwise the feel of the various weights is great.