I have a Logitech Extreme. It's got a steel base and it's meant to be a competitor to the Microsoft Sidewinder Precision Pro. But I think it's alot better. It's steel base makes it much heavier on your desk, the SPP seems plastic and cheap. The springs are much firmer and it has a rubber boot, so it feels far less flimsy.
The buttons are different, the hat has two buttons on each side, so your thumb can control 4 buttons instead of the SPP's 3. However, where the SPP has 5 buttons in a 4/1 arrangement on the base, the Logitech only has two. I like the logitech's sliding throttle rather than the SPP wheel/dial. The only thing it looks like a metal hinge or something, who knows what they were thinking with that.
Anyhow, it's also usually alot cheaper at the store than a MS stick, and the digital control with the stick and the twist in the Z-axis is just as precise, which was the whole point of the MS stick.
XX