I bought this at the same time as the UnderArmor V-neck compression shirt (also reviewed). I thought the only difference would be the coverage (higher neckline and no arms), but it also has a breathable "panel" on the sides. This does aid in comfort, and does something logical and unique, it reduces the compression in the chest area. In general a good idea for a NON-WORKOUT shirt, and I wish their V-neck version had this feature. That being the case, not having sleeves and not compressing anything but the core (a little), doesn't make it a great workout shirt (very little compression). There are other products that will just compress your core, and do a better job at it.
The lack of sleeves and vented sides would make it a great "dress" T, but the high neckline with colored stitching and large branding on the back of the neck doesn't lend itself to that.
Overall, seems well made, and I'm glad someone realized that the chest doesn't generally need compression. However, I'm not sure when I'd use this. Not enough compression for the gym, and a bit odd to wear it (showing prominently) under a shirt (maybe some people would like that. I guess you could wear it by itself, but I'm not sure where I'd wear something like this, other than the gym, and it's not ideal for that.