I suffer from mild RSI: a warning to stop, but one that goes away when I do stop. The trigger is using a mouse for extended periods. The alternatives for general everyday computer use aren't great for my work habits, which center on precise pointing and clicking, so I'm in the bad habit of mousing until the ache begins, stopping, then picking it right back up later. I'd never tried a vertical mouse in the past because my malfunction is mild, the ergonomic improvements aren't clear, and they tend to be expensive. But the OJA Wireless Vertical Ergonomic mouse is only $6.99 on Amazon, so I decided to give it an impulse-buy shot.
I imagined it would be an absolutely terrible mouse, but expected that I could at least use it long enough to see if the enormous vertical wedge shape of it would be good for my hand. As it happened, this thing is probably good enough to keep, with only a couple of slightly annoying issues holding me back.
From the design, it appears to be a knockoff of something by Logitech, with dark gray satin plastic, chrome trim on the mousewheel, and large dimensions all around. It's wireless (a provided USB dongle fits inside the mouse for storage) and charges via USB cable. There two thumb buttons in addition to the usual left, right and wheel buttons. There's a DPI switch and an a power toggle underneath. The photos on the Amazon page depict it with FCC and CE symbols that are not in fact present on the device. It is instead marked with the text "wireless charging the mouse game."
It's OK. It's not awful. It's like the half-decent mouse you might find bundled with a cheap desktop computer. It doesn't track quite as nice as even the cheapest Logitech or Microsoft mice, and it doesn't physically glide quite as smoothly, either, but it's half their price and in the large and unusual "vertical" ergonomic format. Frankly, if you've been thinking of trying it, it's perfect in that role, as a stepping stone before committing to something like the $80 Evoluent 4.
On the ergonomic front, it's a clear improvement for me, but it doesn't quite fit right in my small, Trumpesque hands: it's as if they formed it by having an average American man gently squeeze a blob of clay, then loaded the model into a 3D app and smoothed out all the nobbly bits. Note that it (and other inexpensive models) are not quite as vertical as the pricey Evoluent model, either, which is presumably patented and more thoroughly scienced.
The problems: it takes a second to wake from sleep, and it sometimes just goes hayware. The former is just how things are, and not really a problem, but the latter is hard to figure out. Is it a battery power issue? A wireless interference issue? A USB dongle issue? It's not a killer by any means, but it happens often enough to annoy. It's fixed by plugging it in and using it wired, even for just a moment.
If they get to me, I might try Anker's $20 vertical mouse -- a price point that's still cheap, but as with wine, seems to promise something more satisfying and robust.