Dr. Zoidberg said:
It's hit and miss.
Since PC controllers map their buttons and axes differently it depends. I don't have any standalone PC USB controllers but I've successfully used various PC adapters on the PS3 with various levels of success. I've played Gripshift using a PS2 and a Gamecube controller through adapters. These USB adapters are just turning whatever controller you plug in into a generic PC USB controller which the PS3 recognizes. I've even gotten a Saturn pad to work in the XMB without issue.
Here's the rub:
1) Obviously, these controllers don't have the "PS" button on them either, so PS2 BC games can be a problem as the system disconnects all controllers when you launch one and requires the "PS" button to reconnect. They make specific PS3 adapters for PS2 controllers that have the PS button on them.
2) Some games require the analog stick for navigation, and if the controller you are using doesn't have one (Saturn) or it's mapped oddly then these won't work.
EDIT - As for the specific controllers you mentioned, you need to make sure that they don't require specific drivers to work in XP. If they do, they won't work on the PS3. Also, don't expect the "rumble" funtion to work either.