Bests & Worsts Reviews from Amazon

This is certainly a well made unit, and its ergonomic "wave" form really is pleasant when doing hours of writing, as is its rubbery, vaguely faux-leather rest for the heel of the hands. Having also just got the new Logitceh MK 320, I'd have to say it delivers very similar quality in most ways to this, and is probably a better wireless value for the average user. If you write all day, however, the MK 550 might have your name on it. Like the 320, this is a breeze to set up: pull out the tabs under the pre-installed batteries, plug in the (super small) usb wireless receiver, and off you go. That's nice. (The included cd is for customizing some of the function keys and won't be used by many is my guess.) The first thing you notice about this keyboard is how large it is, almost 50% bigger than the average wireless kb. Most of that room is used by the palm rest. If I was a perfect touch typist, this might be the ultimate kb; it seems to be designed with the pro typist in mind. But I'm merely ok, and one thing I've already noticed here is that the wave is a little disconcerting when you move your hands about a bit, as I do. The contours make it a bit odd coming down on a key at an angle. I find myself longing at times for the smaller, tighter, flatter setup of the 320. If I was a perfect typist who rarely looks at or moves my hands, that might not be the case. Which are you? The mouse is much larger than the 320's mini-mouse, which bothered some reviewers here, but didn't faze my medium large hands. This is a heftier, contoured mouse and certainly feels more solid, with a smart pair of buttons for your thumb to go back and forth between the previous pages. (Without cookies on, this could be a negative, though...whoops, I accidentally lost my whole document!) My qualm with this mouse vs. the 320's is that you need to move it twice as far to take the cursor from one edge of the screen to the other. I prefer the tighter ranger of the smaller mouse, but many might prefer this mouse for its more standard size and contours. All in all, as an ergonomic keyboard this is easier to use than a split kb for a new user, but the wave feel does take some getting used to for those who always use a flat kb. The back tabs also lift it up a fair bit, so much so that your hands are angled a little higher than the 320 or most kbs, which if one is typing all day might take more blood out of the hands than desired unless your desk sits very low. I find myself having to shake my hands out a bit more using the 550. But the keys have a nice travel, maybe a tad long but with a very nice spring to them, and they're a pleasure to type with. The dedicated function buttons for wmp and your home page etc from the 320 are here too, mute and volume included, and a few extra ones as well. I like that feature a lot, as I listen to music all the time. Logitech designers, well done. Every kb needs those. All told, I think this is a very fine keyboard for the serious, all-day typist. The mouse is also excellent. They're both quite solid and feel like they'll last for quite a few years. And if the promises are correct, battery life of over two years for both kb and mouse is pretty amazing. The wireless aspect makes life a lot easier as well; being able to lean back and use the kb in your lap for a while is a good option, especially if your back needs a rest now and then. If you don't type too much, just for emails on occasion, I'd go for the smaller 320 kb/mouse combo at less than half the price. But for those who almost live at their computer and do hours of writing a day, the MK 550 could make your life a whole lot easier. [Edit: 4/21/11. Just thought I'd share battery life specs; the two alkaline batts included with the keyboard just went dead after roughly 750 hours' usage. Which seems a pretty fair deal, all told. I'll be replacing them with rechargeables, as with most all of my devices. I left the originals in so I could share their lifespan here; hope it's useful to some folks. Still enjoying using the keyboard. It's a good one; no complaints at all.] [Edit: 8/4/12. Still on my second set of batteries, with daily use of a few hours most days, for both the keyboard and mouse. Both still work as well as the day I got them. I've also grown accustomed to the shape of this kb, and really enjoy its wave form now. Plus none of the letters etc are worn off at all, even after thousands of hours of typing. Ain't it nice when you actually get value for your money?]