I've got a Cingular 8125, and originally Google Maps didn't work very well on it. I had to run it in that MIDlet Manager, and if I tried to switch to the satellite view it would give me an error stating that my phone didn't support jpgs.
This version works MUCH better! First it gave me the option of installing to my SD card instead of the internal
And now both map & sat view work perfect. Oh and using the stylus to move the map is nice.
And esp if you use a wireless connection it seems to run pretty smooth, and traffic works too.