I just received my first "custom" (actually MTM) shirt from Land's End, and I really like it. I've only ordered RTW shirts in the past, so I can't compare it to Kabbaz's shirt (maybe someday), but I am impressed with the fit. It's not blousy around the waist, and the material is good quality, even though I ordered the cheapest material for my first one. You have a fair number of styling options, although not as many as Janzen does.
The one drawback is that Land's End has mostly solids, and most of the few patterns are fashion-forward.
If you order, click through the link on Andy's home page.