Shopping cart: More similar products or less similar products for better seo?

[Salim]

I am working on a shopping cart and I have a doubt about products. Products are airport transfer products like

From Heathrow Airport to Kingston

From heatrow Airport to Croydon etc.

end i will have different service styles like private, shared, shuttle.

My question is about seo matter? Which way is good?

WAY ONE

Creating categories for each type of service and adding transfers under it. Like

Private-transfer/from-heathrow-airport-to-Kingston-private
Shared-transfer/from-heathrow-airport-to-Kingston-shared

Way TWO Having city categories and service categories adding only one product by choosing city category and service categories and giving an option to user to chose service types under one product.

london/from-heathrow-airport-to-Kingston
Private-transfer/from-heathrow-airport-to-Kingston
Shared-transfer/from-heathrow-airport-to-Kingston

Which one is better for seo? If you have any other suggestions please let me know.
I am waiting your replies

[Jake]

Using the Google keyword tool (now requiring you to have an Adwords account) is the most direct way to find which phrases are searched more often.

Adding some rich original text, like how to articles for your visitors, may be a bigger search rank factor than the minor naming variations.