Defender Extreme Turbo (PRO). It's 100% compatible with (all) PS1 games.
(same thing about PS2 games, but I have no PS2 to test it)
That wheel also has 3 modes:
1. Digital (PS1 Digital):
Default mode on this wheel. Has no axels.
2. Analog (PS1 Analog):
On PlayStation you have one axis (for steerling wheel), on PC you have two (one more axis is for pedals... both pedals... wait, what!?). The most recomended on PC.
3. Race (PS1 Negcon):
On PC this mode is most useless: L1 and L2 disappears, R1 and R2 are acting like one buttton, number of axels is still 2.
But on PlayStation this mode is best: this wheel here has 3 axels (one for steering wheel, two for each pedal). L1 and L2 doesn't disappear, but there they're acting like one button, just like R1 and R2. (also, NFS4 asked me what controller I'm using: steering wheel or another (Negcon). But it hasn't effect on calibrating, it's same for both controllers) The best mode for PlayStation.
For now, it's the only wheel that I have seen with handbrake and PS1 compatibility. And also it hasn't ugly (for me) racing wheel design, that's overused by Logitech (it has only few wheels that does not has that design, one of them is Driving Force GT).