I wouldn't recommend them. They offer suits at a number of price points. I chose the mid-price point and the suit construction is fused. The highest price point may feature canvassed suits, I don't know, but then the price is comparable to WW Chan, whose suits are superior in every way. I bought my Grand Tailors suit over two years ago, before I started reading SF and was entirely ignorant about quality clothing. I learned about WW Chan shortly afterwards and haven't looked back.
Also, there's no unsubscribe feature in Grand Tailors' email messages, so I keep having to delete their correspondence every three months or so.