Helo @idea21, how are you doing?
Look, I had a problem like your, and the best way I've found to Export/Import my Products (and Categories, and attributes, and images) was using eMagicOne Store Manager for Magento. It's a (paid) software, but you can signup and get 14 days on trial mode (with full access to all features).
If you want to try this software, you had to pay attention in some tricky steps to do it well.
- Use Connection Wizard to Connectec to your OLD site;
- After connected, Go to 'Tools' tab and click 'Get Data From Web';
- After your data download finishes, you must click in right tab (which have the software icon) > Import / Export > Produtcts
- Backup your DB
- Follow the steps.
Once your Import was done, follow this steps:
- Use Connection Wizard to Connectec to your NEW site;
- After connected, Go to 'Tools' tab and click 'Get Data From Web';
- After your data download finishes, you must click in right tab (which have the software icon) > Import / Export > Produtcts
- Backup your DB
- Select Import & Follow the steps.
- After the tools finishes the import go to 'Tools' tab and click 'Post Changes to Web'
I hope it's solve your issue.
In time, please ignore my grammatical, I'm not a native English speaker (writer, in this case).
Best Regards!