The PS3IRX1 is the original device Mike Muecke designed to allow control of the PS3 with a infrared remote. It is a really small device that plugs into one of the USB ports on the front of the PS3 and allows a infrared remote to perform any command that you can do with a game controller (except the PS Home button).
The PS3IRX1 cannot turn the PS3 on with your remote, you will have to push the buttons on the PS3 or use a controller to turn it on. The PS3IRX1 will take up controller slot 1 if you turn the PS3 on with the buttons on the machine. You can easily re-assign a game controller to slot 1 by hitting the PS Home button on the controller and selecting the re-assign controller option.
If you have the latest firmware for the PS3 you can use the PS3IRX1 to turn the PS3 off. Sony added a power off option to the Cross Media Bar (XMB) in one of the latest firmware updates. I have posted a series of commands in this forum that you can include in a macro to automatically shut the PS3 off using this menu option.
The major commands that you will not be able to use with the PS3IRX1 are PS Home, the four color buttons, angle, audio, subtitle, and eject. Most of these commands can be accomplished if you use the triangle button to bring up the on screen command list and select them from there.
The PS3IR-Pro allows full control of the PS3. It includes all of the commands on the Sony Bluetooth remote including the color buttons, angle, audio, subtitle, and eject. It also supports the PS Home button, and can turn the PS3 on and off. With the latest firmware Mike has added a power tracking feature that helps prevent accidental power up of the PS3.
Here is the main Schmartz page where you can read up on the two products.http://www.schmartstuff.com/
I hope this helps.