Background
Over the years, I tended to gravitate towards mid-priced wired mice. I knew the really cheap ones would die quickly, and much more than USD40 seemed an awful lot of money to spend on mice. Not like it was a keyboard or anything
Never cared for wireless ones, because I expected them to let me down at crucial moments (and when I finally got one of those Microsoft Touch Mice, damned if it didn't do so, burning through the pack-in batteries in less than a fortnight!) If I had a 'favourite', it was probably the Logitech M500-- a sensible shape and reasonably competent construction. Even when I finally admitted to coveting a friend's G7 enough to buy the wired analogue (the G5), I ended up going back to the M500.
Eventually I got into trackballs (which ends with a conclusion that it's okay to spend a small fortune on a CST), and the M500 eventually made its way to the office, where I used it until the feet came off due to three kilos of schmutz impacted into them. So, of late, my mouse exposure has primarily been a pack-in HP optical mouse at my office desktop. My expectations are, therefore, quite low.
First Impression
I was immediately fairly comfortable with the shape of the Sentinel III, being fairly reminiscent of the M500. It's contoured enough to fit the hand, without some of the more extreme bends that could be uncomfortable over long periods or unaccomodating to extra large or small hands. The surace is just hard plastics, possibly painted, and there are several seams. I expect over the years to see a bit of dirt collection there, but it won't have the issue of the surface wearing or peeling off the way some premium mice do.
While the main switches are satisfyingly clicky, the side buttons have an softer hollow snap- not quite dropping down to "tactile only" but nowhere near as loud as the main buttons.
The build quality seems solid enough, but at the cost of it looking like the whole thing is permanently snapped/fused together. It does not look like you could trivially disassemble it without damage. It has one of those nice loomed-look cables-- all the trend, but do they collect more dirt than a similar smooth cable exterior?
Software
In an ideal world, input devices will not require drivers. When you get too dependent on drivers, it's one more thing when setting up a new machine, or one more thing to say 'but it won't work in my OS/2 3.0 install!'
I think CM made a reasonable compromise on software here. They wanted to pack a lot of functionality in here: all the buttons being configurable, colour and DPI adjustment-- and it's well beyond the scope of configuration by pecking on the little screen. However, the beautiful thing is that the software doesn't require a permanent presence. It doesn't launch at boot, and the configuration is stored on the device. I could see, for example, programming it once on a Windows box even if you normally use Linux.
I have a particularly awkward case-- being split in affections between this and a Kensington Expert Mouse being used left-handed -- it may make sense to configure the OS for the trackball, then stuff the mouse's configuration with reversed buttons so it can be used right-handed in spite of the OS.
I will call out two minor concerns with the software as-is: The colour scheme-- muted dark grey on darker grey-- gives the impression of disabled controls. (Sorry, I spend all day yelling at people over 'this is a terrible way to design a form') On a more substantive note, although the mouse has two distinct LED zones, there does not appear to be a way to configure their colour/behaviour independently. It's entirely possible I'm misinterpreting the description on the website, and it's only one colour choice, just coming out of two openings, but given how people went crazy over things like the Corsair RGB keyboards not living up to expectations, might want to run that language past legal.
Performance
Now here's where it becomes entertaining. When I took the mouse home, my first attempt to use it was the "naive" approach-- plug it into a socket and drop it on my ordinary Ikea laminate-covered desk. The cursor doesn't budge. Occasionally you get a twitch at the highest DPI setting. But clearly not registering motion in a meaningful way.
So I run my finger over the sensor... some signs of life.
Proceed to an hour of thwapping the mouse, assuming "the sensor lens must have fallen out of alignment during transit", and trying to find a way to crack it open without destroying it. Finally, I try some other surfaces:
Old "Dilbert" comic anthology: Nothing
Final Fantasy XII game case: almost usable tracking at medium and high speeds.
Small copper ingot - perfect tracking. Wait a minute-- isn't shiny metal supposed to be really difficult for optical mice? I'll try some other metal pieces-- an old PC side panel, and a project box case... again, tracks fine... what's going on here?
Borrowed old mouse pad: perfect tracking.
So we can conclude the sensor really just hates a lot of surfaces, most significantly bare desks. This also means I have to get my hands on a mouse-pad. After a week in the post from Hong Kong or somewhere, I finally got one and was able to proceed to review the mouse as a mouse instead of an art object. (Bonus points for people who can figure out the design on the pad-- a nod to one of the few hobbies more expensive than input devices)
The fully-adjustable DPI is a huge win compared to 'a few fixed setting' models-- which will inevitably be too low or too high for your taste. I'm finding 2400 a nice usable choice with a 2560x1440+1600x1200 desktop, easy to whip across the whole screen at once-- while still being reasonably precise.
In looking at this, I will admit, I'm not their target demographic. I have no doubt this is intended to compete with gamer-gear products coming out of Razer and Corsair.
I game, but I typically prefer a 360 or Steam Controller over a keyboard+mouse, but I do spend probably 12 hours a day in front of a PC of one form or another, so I do appreciate a mouse that's comfortable and doesn't get in my way. The fact it throbs a sinister red light at me while I use it is a bonus.
I can see the "program it and the program stays on the mouse" feature being a powerful differentiator to the performance-oriented gamer crowd. "Why are you wasting precious CPU cycles and memory on something like Razer Synapse just to have your macros and LED colours how you want them" or even "the configuration follows you even if you take it to work/use it on your laptop/etc."
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