Both cars have same engine and almost same pick/acceleration and both have excellent ac.I have used wagon r for two and a half years and it is a very practical car ,acceleration/pick,Ac,suspension,power steering ,ground clearence ,fuel consumption everything is optimal in this price range and the best part is i can sell my used car for more than the invoice price because it sells like hot cake these days.Cultus is also a very good car but the price difference b/w vxl wagonr and vxl cultus is alot so i would recommend to buy swift or city if u plan to buy a car in that price range.Best of luck 