The lion's share of supermarkets in Peru are in the hands of the Chileans. Tottus, Saga Falabella (called simply Falabella in Chile) and Sodimac are part of one single company in Chile.
Wong and Metro are part of Cencosud, which is a chain of supermarkets and hypermarkets in several South American countries (Jumbo in Chile, Disco and Jumbo in Argentina, etc.).
Plaza Vea, MASS and Vivanda are all part of Supermercados Peruanos S.A., a Peruvian company. Plaza Vea is the largest chain of supermarkets/hypermarkets in the country, with 38 stores in Lima alone.
My boyfriend works at Metro, so we shop there and at Wongs, as he gets his employee discount at either.
Be prepared to make more than one trip to the supermarket, because invariably you will find that some branches (of the same chain) carry certain articles that other branches do not. If you want Brand X hot dogs, for example (prepackaged), you might find them at Wong Benavides in Miraflores but not at Wong 20 de mayo in San Isidro.
Wong and Vivanda are by far the more expensive of the group. Tottus, PV and Metro are probably a wash when you include everything.
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