[HummerNewbie]

When I read voice guidance, I was thinking voice commands as in you say the address you want. The Z1 has that feature doesn't it? The D1 does have voice guidance and it works fine without the vss hooked up. I know it will increase the accuracy no matter where you are at but I have yet to have an issue without it. I wonder if your location effects the need for vss or not. I can see being in the mountains making it more important. It certainly won't be like being in the rockies but guess I will find out when we head up to Tellico. Every morning it is off by a couple of blocks but is back on track in a couple of minutes. Not going to get lost within a couple of blocks from my house so not too worried about that