The first one and the second one seem to be the same thing except for the price and maufacturer.
At the moment I'm going for the first one simply because its the cheapest and they all seem relatively similar with 4star reviews at least. The one problem is the LED indicator; apparently its untrustworthy which is imo a pretty big headache. So which of the four have people actually bought and would recommend? Is there another one I've missed? tia!