CRM – Copper or Streak or Alternative?

I work with a team of sales agents who are protective of sharing who their customers are (to their contemporary colleagues) due to the client poaching nature of the business.

Looking for a CRM that can:
1. offer anonymity (although using the CRM) to each agent so that one user cannot see the leads of another user. if a lead or account exists in the CRM, looking for some functionality where the user trying to add this existing lead will be met with an error stating that lead already exists in the CRM (based off the email address attribute or first and last name attribute).
2. dashboards/KPIs – being able to to track per agent how many emails sent/received, quotes sent, deals closed, etc.

1. integrates well with Gmail – if all CRM activity can live on the Gmail UI, that would be ideal. Have done some research and have have read good things about Copper and Streak.

Which is the winner? Any alternatives? Thank you.