I've lived in more than one Spanish speaking country and to this day I still have difficulty getting people understand me when I say "tres" (3). Usually I hold up three fingers whenever ordering 3 anything...
Approximate pronunciations are all we can do sometime ;)
Pax Night and day you can find me Flogging the Simian
I'm going to stick with the x though... Although you are correct, I suspect that difference may be a little fine for most US natives to master right off the bat. "Ideas or the lack of them can cause disease." - Kurt Vonnegut
