The i-rocks RF-7550A 2.4GHz Cordless Optical Mouse is a decent mouse created by a company that doesn't believe in the famous marketing dictum that to keep your customers happy you should "under-promise and over-deliver."
Instead, i-rocks prefers to take the opposite approach.
Fortunately, the affordable RF-7550A is a good mouse--not a great mouse, but a solid five-button RF-wireless unit that at 3.5 ounces is heavy enough to be comfortable but light enough to be portable. Its humpbacked body is easy to grasp, its 800 dpi LED tracking is acceptably precise, and its heavy metal scroll wheel is a pleasure to use.
But back to i-rocks's over-promising: According to the RF-7550A's manual (which is poorly translated--one sentence, for example, suggests that "If the light not work, please re-check the installed batteries are collect or not"), the two well-placed thumb buttons on the mouse's left side will move you forward and backward in your browser of choice. They don't. In fact, unless you've assigned them actions via Mac OS X's Exposé & Spaces preference pane or third-party software such as USB Overdrive (US$20), they do nothing whatsoever. I tried repeatedly to get an i-rocks rep to explain this discrepancy, but to no avail.
The RF-7550A's packaging also makes a big deal about how its 2.4GHz Multi Channel Frequency Hopping Technology provides "8,388,608 IDs" so that you'll never need to worry about interference with another mouse again. Well, I've never worried about it before, and never heard of anyone else having another mouse invade their space.
Finally, i-rocks claims "surpassed battery life," then mentions in small print that you should expect six months of power from the mouse's single AA battery at four hours per day of use--hardly "surpassed" when RF mice such as Logitech's V550 Nano Cordless Laser Mouse for Notebooks claim up to 18 months of battery life. i-rocks also recommends "Duracell or Energizer Alkaline Batteries," but includes a no-name knock-off in the box. And that "Soft Comfort Grip" provided by "rubber coated side grips"? Nope. Hard plastic, all around--maybe a tiny bit of no-slip texturing, but nothing more.
Macworld's buying advice
Don't punish this mouse's engineering team for the excesses of their company's marketing department. The RF-7550A is a quite competent five-button mouse, especially for the price. As long as you don't expect it to live up to its manufacturer's claims, you'll be satisfied.
[Rik Myslewski has been writing about the Mac since 1989. He has been editor in chief of MacAddict (now Mac|Life), executive editor of MacUser and director of MacUser Labs, and executive producer of Macworld Live. His blog can be found at Myslewski.com.]