I am planning on selling a type of cotton thread which comes in a huge range of colours (up to 500 different colours).

I am going to create a custom product template to display all of the colour options on one page so the customer can select how many of each colour and add them to their basket in one go.  


My question is, which way will be best for performance of displaying  this page:

1. Create separate products and add them to a grouped product
2. Create one product and add each colour as a product attribute combination