In reply to UKC Gear: By the time you have eliminated all the times there could be midges, snow, heavy rain or boggy ground and factored in the increase in sleeping bag weight you will have to endure to counter the chill of a constant through wind I have great trouble seeing a use for a tarp at all in Scotland.
I've also discovered first hand elsewhere that tarps are more prone to tearing than tents and the stress put on pegs, guys and other anchors is greater than tents also.
I see nothing to recommend them - just my two cents
One thing worth mentioning about the UV pen is that, unlike a filter, it will not remove suspended debris from the water, so you need a fairly clear water source to begin with. It's a minor point and probably the only places this would become an issue would be where there was very limited water (not the UK!) or you needed to use glacial melt water.
I hate poxy little pots too, if it isn't at least 4 litres, it can't hold enough food for me! 5000 calories a day or you just weren't putting in enough effort :P