The Carrefours on Ma An Shan Lu is much less crowded than the on on ChangJiangXiLu, in my experience.
Ma An Shan Lu is all torn up because they're building a light rail, so it is actually only accessible by Tunxi Lu, but I always tell cabbies "Ma An Shan Lu Jialefu" and they know how to get there.
The foreign goods sections in each one are a little different.
The ChangJiang one has a little refrigerator in their foreign section with Lurpak butter and sometimes cheese in it.
The dry goods section at the Ma An Shan Lu one is bigger, and has Doritos, tortilla chips, and I think more dried pasta and flow and cake batter and things like that.
I like the MaAnShan Lu one better, on account of the less crowds, but also because I live right behind it.
I was driving in a taxi the other night and passed a big Tesco somewhere, I wonder if anyone is familiar with it and whether it has any foreign stuff?
I'm not sure where it is, except that it's by an HSBC bank, which I also discovered for the first time on the same taxi ride.