I use extensively ponchos, military or not while on move.
For shelter it beats anything else as an emergency shelter, also great to reinforce natural material shelter.
The whole point is getting the right balance between weight and durability.
For extensive use I would plan to use something else in addition as average poncho is really too small to be comfortable (well also depends on how tall you are). As pointed in another thread if you get any serious rain it is also a good idea to get some sort of leg covering.
For mountain, open areas I'm using civilian golite poncho.
For forest roughter areas I've been using military ones
mostly BW poncho (very durable, quite heavy) and some nato ones which I belive are based on the US design (belgian, NL: a bit less durable but still sturdy, lighter).
Sorry no pics.