NOTE: Francois of MTBR.com has done a mini write up on the kit, and it includes a review video, beam patterns and lux readings of the system, refer to http://reviews.mtbr.com/blog/ayup-v4-adventure-bike-lights-review/ for further details.
I started to use the helmet and handlebar systems recently for some night rides with the bike gang, though on occasion I commute to work using the handlebar mount. Most of my local terrain in Colorado, takes place on tight singletrack, so I rarely spend much time on open and expansive trails.
Although it is behind in total light output compared to a lot of the competition (refer to http://reviews.mtbr.com/blog/2011-bike-lights-shootout/), it makes up for it with its race breed features. I really liked the use of the Gecko attachments for the helmet mount, as they were easy to use and remove, plus the 1/2 Epic battery can be easily swapped out when it gets drained. They do need to include more additional Velcro pads for different helmets and as replacements. The twin light setup is excellent for the head and helmet, since you can swing them apart to create a double stacked beam, which is tall and long, making it great for tight singletrack.
The long beam allows you to swing your head to the spot you want to see, giving a great expansive viewpoint looking down single track (albeit narrow), and pin point spotting if desired. It seemed sort of silly at first, but it was highly beneficial and functional when out hammering and flying along on narrow trails.
I like that the handlebar mounts are centered over the stem, so that the beam points straight down the trail, or at least wherever I happen to be steering. If I was riding double track or trails that are more expansive, a wider beam would be a requirement, and even though my local terrain is pretty tight, it would still be a nice feature to have some additional width. I have used the bar mount for commuting, and it has worked great, with enough light for the road and sidewalk. Although the handlebar mounts are semi-permanent, I ended up leaving one on my commuter, and the other the night riding bike, so it was much like my GPS mounts, they just stayed where they were needed, so it wasn’t that much of an inconvenience. Since they were zip tied on, they were very stable, and I never had to worry about the light getting loose nor bouncing off track. Taking the light and battery on and off was simple, and the battery’s neoprene pouch protected it, and held it firmly in place. Having the large Epic battery on the front was pretty sweet, and I never had to fret over its storage capacity on my usual rides. In fact, that was a great thing about the entire system, the batteries seemed to last for a long period of time, which made it convenient to leave them on High.
I like that it has a simple High, Low and Off mode, and none of the silly flashing stuff in the same cycle. When I am commuting, I never use the Flashing mode, since I find it annoying and distracting. The rubber covered switch was soft to the touch and had a good positive click, and seemed pretty durable, even with all the on and off cycling during my testing (my kids helped with that).