Well...since this thread hasn't had a post since last January I'm thinking no one here picked up one of these.

I finally got around to picking one up this week, mostly since all 3 of my MS controllers failed after about 3 years for the same reason - rumble temporarily jars the internal battery connection loose. I picked up the $50 pro edition Onza with the adjustable thumb stick tension, and so far I'm liking this far more than I'm disliking it. Here's my list of likes and dislikes.
Likes:
- Adjustable thumb sticks work very well. You have to make a few adjustments before you notice a difference, but I can sy it makes a significant difference for racers. Enough of a difference that I'd now attempt to play F1 2011 with a handheld controller, which is something my son and I abandoned last year with F1 2010.
- A d-pad that actually works - its like a cross between a dual-shock and 360 d-pad. I haven't had a chance to try it with a fighter yet, but I can finally d-pad through 360 game menus with precision - yeah! For sure its not quite as good as my Mad Catz fighting pad, but far, far better than the truly craptastic one on MS's controller.
- Remapable, twin buttons above the shoulder buttons are great. I've mostly been setting them to mimick the shoulder buttons, but I love having the option. This is a great feature for CoD play if like me, you aren't thrilled with pushing the r-thumbstick for melee kills. Each side has its own button and it's just a simple button press on the bottom to set them.
- USB cord is solid and lengthy. It has the standard quick disconnect feature to prevent jarring when someone trips on it.
- Slightly rubberized surface - feels much better than the standard 360 surface.
- Buttons are far more sensitive. That said they take a bit get of getting used to because they're smaller, but definitely an improvement over MS's controller for sensitivity.
- It works with the PC - says so in the instructions. No I haven't tried it yet, but I'm excited to as the sticks seem to have a less pronounced dead zone. I'm going to reinstall GT Legends and GTR 2 to really give it a test.
- No batteries required - yeah! IMO this makes putting up with the chord worth it. More importantly for me, I have peace of mind that the problem that occured on my 360 controllers can never occur with this.

Dislikes - yes there are some:
- Heft. Not a big deal as the difference is slight, but it does none the less feel lighter than the default controller. And that's not just accounting for the absence of batteries. Still heftier than my Mad Catz fighting pads though, which I've been perfectly happy with.
- The cord. Its nice and thick, but its covered with braiding which can make it a bit difficult to coil up. My Logi G5 gaming mouse has the same type of chord and I've had some problems with the braiding shredding and chord kinking. That said, the Onza's chord is much thicker, so its likely to not be a problem.
- Triggers - Their tension is very good -better than MS's- but they're thinner at the downward ends so they feel a bit sharp. I'm thinking this is more of a personal adjustment thing.
- Back and Start button locations. They're on the back edge directly above the head set connection. They certainly take some adjusting to get used to. I can personally say its possible to get used to them, as I've been using [Back] often to view the graphic changes for Halo Anniversary.

All in all, so far I'm liking it more than MS's default contoller.

[Edit] I didn't mention it earlier, but I should of - the force feedback is noisy. Quite a bit more aubible than the default 360 controller. Not a problem for me, but it could be for those who play late at night and have a light sleeper to consider.