The call quality on the non-upgraded bluetooth on my base head unit is great. One great thing about the handsfree setup in this car is you can adjust the default volume of the mic and speakers. I turned both down. The mic was picking up road noise, so I turned it to where I can talk in a normal voice and people on the other end can hear me perfectly without background noise. You'll have to adjust it while having the person on the other end give you feedback. I turned the speakers' default down because people usually talk too loudly on the phone.
That's the key here, talk in a normal (maybe even quiet) voice and the other end will hear you perfectly. Ask people (politely if you want) to talk a little quieter from their end also, and you'll have a great experience with it.
