Bi-directional relationships

I need to know if there is anything wrong or dangerous having a bi-directional relationship between two tables.

I have relationships already established as follows:

Customers have many Contacts
Contacts have many Opportunities
Customers have many opportunities

I want to create Opportunities have many Contacts

Here's why:
Within an opportunity we define everything about the deal, including what we are quoted and what we intend to quote the customer.

My objective is to launch off the opportunity with a button to create a quote, and it will look at the contacts to determine if any of them have a primary (or secondary) role in their Bill to, it would put my name/address in the Bill to section, and likewise with Ship to. In some cases we'll have one name/address for both.

I figure the first step to making that happen is to display a report on the Opportunity and show names where the contact meets one or both criteria.


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Wade Myers
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