I have to agree with others who like them both. I love both of them.
For most TS restaurants, including most of World Showcase, I choose lunch. It appears to be essentially the same food, at substantial savings. My only exception, is Rose and Crown, because I love going there during IllumiNations. But getting back to the two restaurants.
The San Angel Inn is so cool. Actually, I think that the Mexican Pavilion is the coolest Pavilion. The food is good, too, if you like Mexican, which I do.
That is where I think that people put down San Angel Inn - they are not big on Mexican food. Let's face it, Mexican food is laid back, casual food. French cuisine is, well classy. I assume that France is probably the birthplace of fine cuisine. So to get a fair viewpoint on the two restaurants, it should be from someone who likes both foods. But then, what do I know about good food, afterall, I think Taco Bell is good.
Chefs is a very nice restaurant. I avoided it for several trips, because I thought it was too stuffy to bring excited children to. Was I wrong. It is laid back, too. It is now a must for our trips. The only think that I every had, however, are the short ribs. They are cooked in a Cabernet sauce. Delicious. When I find a food I like, I only order it. Take the Sci Fi, for example, I only order the Rueben - every trip. So I cannot comment on anything else. The other thing I like about Chefs is their wine. I love wine, but know very little about it. At Chefs, you can try a glass or two. If you like it, just remember to write it down, so you can buy it at home.
Probably not much of a help - since they are both worth trying.
Have fun,