PSP coders Skity and Stewart have just announced the release of version 2.5 of their Speed Reflex homebrew. As its name implies, Speed Reflex is a Lua-coded racing game built to test your reflexes. The game also features a stopwatch to help keep you keep track of your best time. As for this version's latest chagnelog:

Difficulty of the play increased.
The possibility of choosing the language between English or French functions, the Appropriations remain however all the same in French.
Correction of some bugs.

As for the controls

"X" - Slow down and select
"O" - Start again the part
"Start" - Return to the menu
"R" - Confirm the part in the play

This download is for PSP firmware 1.50. To install the game, connect your PSP to the PC via USB, unzip the corresponding file bundles, and drop the unzipped folder into your PSP. Enjoy the download.