Another Brit instructor throws himself to the Lions....
In several years of instructing I've "converted" 2 US trained PPLs, 1 NZ trained PPL and flown with a large number of UK and European pilots. There's always going to be a range of piloting skills due to natural aptitude but, in my limited experience and from this very small non-European sample, (gulp), a 100% of those I've flown with who were trained in the US were at the lower end of the skill range. They both got their FAA licenses in minimum hours.
Typical problems were a total inability to use Visual nav techniques, poor approach speed control, abject terror when a wing dropped at the stall and a lack of "captaincy".
I've flown with others who have done some training in the US and heard awful stories.
I'm sure that there are a large number of excellent pilots who trained in the US but it's just that I haven't met them yet and we all form our opinions based on our own experiences.
Is there any space left in that bunker?