We,, it ain't instant. In my educated SWAG, I'll estimate it at ~ .2-.4 seconds for just the "Dashboard" display with 5 gauges. I haven't played with it all that much.
Automatic Bluetooth pairing, Google maps, HUD: lots of very cool features. All for $38! (Plus the tablet/Android phone, of course).

I do wish I had a 7" tablet, though. 10" is pretty big in our little cars! I found a mount that works, but I'll have to modify it (lengthen) to put it right where I want it. Centered above the radio.