Looking to change from my Yahoo Store to something else and need a new shopping cart.

Looking for suggestions.

Here are a few things I need:

1) Cross-selling feature. Suggests other items to customer.

2) Export data to Excel, and Quickbooks

3) Sales tax report (I can't believe Yahoo Store doesn't do this)

4) Real time shipping calculation (UPS, DHL, USPS)

5) Sales tax calculation at time of order

6) Compatible with PayPal Website Payments Pro

7) Store and retrieve past orders

8) I want a service, not cart software

Other stuff that I probably take for granted now

I currently use a merchant account, but I'm looking to switch to PayPal payments pro because I believe it will be less money over all.

Any suggestions which carts to look in to? There are so many it is a full-time job searching them.

Thanks!