I've been using Firehouse strobes for over a year now and own 4 ARC V's, one ARC II and two colored mini strobes. It's fair to say I have some experience with them. For the most part I love them and recommend them though they aren't cheap. The kit comes with a USB cable for charging and velcro.
If you do not keep your strobes mounted to your drone and remove them frequently DO NOT USE THEIR VELCRO
I would highly recommend using your own heavy duty velcro or some other means. The velcro they provide loses it's grip after multiple installations and removals. I have lost two strobes, where it just spontaneously fell off the drone's arm in flight and one in a very minor crash where I did not find the strobe. Perhaps I can't necessarily blame the velcro for the latter loss, but there have been later incidents when I've just been handling one of my drones with a strobe attached and it just fell off.
I keep a stash of heavy duty velcro on hand and can tell you that what I have just holds on like a bulldog onto a bone. I have had no incidents of incidental release after having switched to my own velcro. Also, if you're mounting strobes on the arms, I have found a good way to mount them or great way to reinforce velcro mounting is with thin elastic hair bands.
Elastic hair bands
Again, while pricey, the Firehouse strobes are about as bright as they come in this size. The ARC V's are highly recommended.
BTW... I did an informal test of the brightness of the ARC V's vs the ARC II's. I took them into a dark closet and put each on the constant light mode (separately of course) and measured the output with a Minolta FlashMeter V (in ambient mode) for brightness. The difference of the brightness at the exact same distance was indiscernible, about 1/10th of a F stop. I can't say if one is brighter than the other in the flash modes, but the bezel on the ARC V really helps visibility as it refracts light in a much wider angle than the uncovered ARC II.