Without knowing the food you will drink it with, your personal likes and your budget it isn't possible to answer your question. Rimping and Food Hall in Festival have decent selections but lack knowledgeable staff to guide you. The very best place with the biggest selection and knowledgeable staff is Enoteca, located at the rear of the 5th Avenue office park on the 1001 near Meechok Plaza. They have more old world than new world wines and their prices are surprisingly reasonable given the quality available. Personally I see no need to spend more than 2000 baht on a really well made enjoyable wine.