Pheonix Z may probably stand as my favorite Phoenix modification. The extra option of inversion gives it a new feel. The spaceship also looks much more sophisticated.
Graphics: 8/10 - Great Enemies and attack animations.
Attention Span: 8/10 - This is pretty awesome. Especially when you download levels to go with it. The high score system plus different diversity of levels keeps me occupied for long periods of time.
Ability to Pick up and Play: 10/10 - Not hard to do, it shows you pretty much exactly what to do.
Bugs: 10/10 - Bug-free.
Overall: 9/10 - Very great game. Highly recommended for new calculator users, as it gives insight on the capabilities of the TI-84. Easy to install, too - no complicated ungrouping or anything like that.