Shaw's Crab house vs Mitchell Fish Market
I really like both places, but I would have to give the edge to Mitchell's (leaving aside the distance issue in your case, which favors them as well, obviously). Both have very good seafood, very fresh and cooked exactly right. If you're just getting something fairly plain, say a grilled filet of your favorite fish, it would probably be a toss-up; both places do it well. The reason I prefer Mitchell's is that I really enjoy some of their more creative preparation styles. Their kung pao calamari is excellent, and they have a "shang hai" style, steamed in ginger, that is wonderful. I like some of their combination platters, too. However, I would give Shaw's the advantage on desserts. So all in all, I would give a slight edge to Mitchell's, but I would also suggest that you take a look at their menus (see links below) and see if one appeals to you more.
Agreed, have eaten at both (Mitchell's in both Michigan and Glenview) and like them both with a slight edge to Mitchell's. Maybe it's just because I eat Shaw's quite a bit and, while it's always great, a little change is nice. Mitchell's reminds me more of East coast than Shaw's. Also, if you're in North 'burbs, no need to drive to Schaumberg or d'town to Shaws.