CRM has allowed us to keep all of our data in one place that is easy for all users within the company to view. I came into the company after they had been using CRM for about 4 years. They have all said that since we have used this it has helped us control work processes better, it has allowed us to be able to track things so much better, and has been something that has helped unite many processes that used to be all over the place.
We are currently using CRM 4.0 and are planning on upgrading in the next 18 months to the 2011 version. Support for 4.0 is almost all but dried up. Understandably so. Some of the customization we have done, and a plugins we use, are now contained within the 2011 version so we are looking forward to that upgrade.
We use an email marketing company as well, and they primarily support the 2011 version, but their product connects and is integrated within CRM. This is a great benefit as well so that all of our marketing information can be contained in one location.