i have a couple grail items. i find that thermal is tts (cuz it stretchs), and that the tees run smaller (i bought my larger size of the the two sizes that i wear). i love the quality of grail and i'm very happy with my purchases. i would definitely buy one amazing top rather than two-four so so tops. hth!
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"i tell you one lesson I learned
If you want to be something in life, You ain't gonna get it unless, You give a little bit of sacrifice, Oohh, sometimes before you smile you got to cry.." -The Roots
I'm obsessed with Grail. I have six shirts and they're my favorite things to wear. They're so cool and comfortable and definitely worth the price (although I try to buy when I have a code). I agree with shopgirl82 about the sizing.