I spoke with a guy last week that just rotated home from Iraq. He's a Captain company commander in a Ranger battalion that has served 2 tours in Afghanistan prior to his tour in Iraq so I think he's pretty qualified to have an opinion on the matter to some degree. I wont mention what he said about foreign forces (conventional or otherwise) that he worked with, for the most part as units he was underewhelmed by their capabilities with a few rare exceptions. He worked with quite a few some extensively, some just once or twice. For the most part he respected the individuals themselves, and their committment to duty and their intestinal fortitude. So as not to start flame wars that's all I'm going to say regarding foreign forces save one.
The good captain did work ALOT with US forces however and since I'm an American my comments good or bad wont be seen as any sort of flame. Reallize these comments are made in the context as viewed by a VERY experienced Ranger, who probably see's things a bit differently than others in the spec war community just as a SEAL or Green Beret would view things a little differently. His comments are thus:
US Navy SEAL's. Fantstic individuals, fantastic as a unit. Formidable in every way. His only criticism was that their planning was somewhat sketchy. He did feel however that this was due to the fact that SEAL teams train as a team, and train so much so hard that each guy on the team know's what the other is going to do. Not a problem for the SEAL's working alone, sort of a problem when working with others.
Delta. The creme de la creme. He said they were again very formidable and probably the best trigger men that ever ran CQB. But that's what Delta does. He also felt they were prima donna's owing to their notoriouty and the vast amount of goodies they get whenever they want. So they were more difficult to work with than they should have been.
Special Forces. He was very impressed with SF, and couldn't think of anything negative to say. Their speciallty is somewhat outside the norm from the US spec war community because A teams are expected to operate with indiginous peoples with not a whole heck of alot of support. They are in a word, unique because SEAL teams, Delta and the Rangers are pretty much dedicated trigger men.
Finally, his opinion on who the best of the best was, he didn't hesitate to say SAS. He said they were a combination of all of the good things the US spec war community offers, all rolled into one very neat package. He was very impressed with the individuals, and the units as a whole. He was also impressed with their helpfullness, patience and unassuming mannerism. In short he said, they were the consumate experts in every way, shape and form.
While this person may not be the "know all" to judge such things, he's probably better equipped to make a judgement than any of us here are. Food for thought.
