This Runpaca shirt is definitely one of lightest weight shirt I have ever tried on and it's insanely comfortable as well. This has to do with the fact that parts of the fabric are made up pima cotton and the secret sauce is 2.5% alpaca wool; I do believe that the fraction of that alpaca does the wonder of odor resistance and insanely soft to touch as well!
Don't take this shirt lightly for just as a runner shirt, you can wear it around town too !But beware, there's a red stripe that run down the middle of the back so it stands out more than your usual shirt. I would say that's the only downside of this shirt but other than it's great and it feels natural as well. It doesn't has any sheen to it and does not feel synthetic at all.
I solely wear this for running in all kind of weather and it has served me well on all runs thus far. I usually end the run being drenched in sweats and yes, my sweat weights it down a whole lot but it dissipates after leaving it out for about 4-5 hours then it'll be good as new.
Definitely recommend this to all runners and casual wearers out there!