The shirt truly is aweseome. Two of these shirts I wore for 3 months during a trip to Asia. It could go many days, probably a week or more, without needing washing from noticable dirt or odor, and I was wearing in dirty and dusty areas. Washes easy and lays flat to dry. It dries quick and is incredibly soft. However, in 90+ degrees the shirt is WAY to hot. I think it is also entirely too hot for gym or yoga wear. I also will also not wear it hiking or running if it is over 80 and sunny. Something to keep in mind.
I have 10 Ibex shirts, as well as a couple Smartwool and Icebreakers. My Ibex 17.5s are my absolute favorites. They feel like silk -- less scratchy then the competitors. Most importantly, they are bulletproof. I have had one of my 17.5 t shirts for about 3 years now and worked out it in twice a week for at least two of those years. It still looks like new. I've worn that same shirt during dozens of hikes and days backpacking, with no wear or pilling on the shoulders (the Smartwool shirts lack that durability). They probably run large -- I'm 6'6", about 240# and can wear an XL. Sure, I wish Ibex was a bit less expensive, but, with Ibex, you really do get what you pay for.