Feature Receiver Disappointing... Best To Go For Text-to-speech Feature Or High-sensitivity Receiver With A Garmin GPS?

Best to go for text-to-speech feature or high-sensitivity receiver with a Garmin GPS? - feature receiver disappointing...

I am narrowing my research, I would like to get GPS. Now I am between the two, one broken, that the function has a highly sensitive receiver, but no text to speech, and another, and vice versa. What is more important? The high sensitivity "device really make a difference? Thanks in advance!