Its more down to what type of cycling you do that should decide what type of lights are for you. Amount of time riding in the dark is the main thing, I do a lot of long distance riding in the dark, so any lighting system which only provides a few hours light is of no use when you expect to be riding at least 9 hours or more in the dark. A work around is to carry more batteries, but that is more weight and if they are rechargeable's, then you cannot dump them to shed weight. If you only ride for a couple of hours in the dark, then those lighting systems from Amazon are fine, but always bear in mind that disasters happen so a couple of punctures, mechanicals etc can keep you out longer in the dark so always try to keep a reserve of an hours riding time to cover such shortfalls, or carry a small white backup light.
I prefer the small cheapish LED lights that take a couple of AA batteries, but they are of no use when speeds get high on fast road decents when you cannot pick out pot holes etc till you hit them so I have a Magicshine fitted o9n the bars as well which I turn on for those moments, its battery life is just over 3 hours but will last me all night when I use it when needed.
