Addendum: Logitech Control Center software
So, I tried the Logitech software. I really gave it a shot, I swear. It did well for the most part: it didn’t brick my machine at boot, or break any apps that I could tell in the few hours it was installed.
But there were some glaring bugs.
First, what’s the most typical thing to do to a mouse with two scroll wheels and five buttons? You customize the buttons and scrolling to do certain things by default, across the system. You’re allowed to do that, but as soon as you make some custom setting set for, say, Firefox (using that side, snap-back wheel for switching tabs is amazing), you have to re-do your other button settings.
SteerMouse gets this one right. You set your system defaults, and then on a per-app basis, it has an extra option for each button: “Same as Default”, or whatever action you want. Bravo, I say.
Second, scrolling speed was busted in Firefox. There was some weird conflict between the software, the OS X default scrolling speed, and Firefox’s idea of scrolling. When I slid the scrolling speed slider toward “Slow”, it moved more lines per single click of the wheel. Yet, counterintuitively, when you spun the wheel fast, you got less movement than a single click. Busted like a cheap piñata, I say.
Third, and maybe this was just me, I couldn’t get the tracking speed and acceleration to behave. It just felt “off”, even after multiple minor tweaks.
So, after an uninstall of LCC and a reboot, I installed SteerMouse (after another reboot, jeez). I love it. It does a fantastic job of customizing the buttons, nailed the tracking speed (different acceleration curve, perhaps?) and even lets me control the free-wheel vs. click-wheel engagement speed of the main scroll wheel (albeit, after running a defaults write command, followed by a logout). I’m going to give it one more day of testing to make sure there’s no deal-breaking bugs, and I’ll be happily paying for a copy of the app.