Ive been using that type for the last year, and because they’re cheap enough, I have several pairs.
They are now just a generic type and everyone sells them ~ cheaper on ebay.
They’re the only rear light I use on my bikes now.
I was a bit worried about the shorter runtime, but I only use/need medium flashing and you get around 5-6hrs. You just need to remember to charge them after a ride or two.
I really like these because they have a 160-180 degree beam display/angle instead of the usual one that just put out as much light one one direction.
They are also good for group rides, as you can lower the power and not blind your mate who is riding on your wheel.
Oh, I tested them till they run out and I found that the light went dimmer and didn’t just die leaving you with no light.