The only way to get good mayo is to make your own. With an immersion blender it takes only 2 or 3 minutes. All the materials are available @ City Super. Here is the recipe:
Mayonaise
2 egg yolks
1 TBS lemon juice
1 TBS white wine or champagne vinegar
¾ tsp salt
1/8 tsp sugar
1 tsp Dijon mustard or hot English mustard
1 cup oil
½ cup olive oil
Put all ingredients in the blender beaker
Let eggs settle to bottom
Hold stick blender against the bottom and give it 2 second pulses until it starts to thicken at bottom.
Increase blender speed and move around in mixture until it has completely thickened