Sorry to hear your BT is horrible. I have the Z130 in my 2008 Corvette Z06. The car is very loud. My BT works great. People tell me I sound loud and clear. I hear them perfectly. My phone is an iphone 4. Perhaps the BT problem was related to the microphone location or maybe your cell phone?
As for GPS systems, they all have their issues. I seldom trust them 100%. They will eventually get you to where you want. I still like to check online before venturing out into the unknown. Good luck with finding a new system.