Jerrico
My main concern with the "one three (thirteen) thousand feet" type phraseology is that stating of the numbers in two different forms is required because people have been confused in the past.
If the phrase "descend to altitude one five thousand feet" is clipped/crossed/garbled/misheard, then an aircraft may descend to five thousand feet (or potentially one thousand feet). This problem is solved by repeating the cleared level in the "fifteen" format - adding to the RT loading, about which another thread is complaining!
In the UK we have FL150 and (for most users who would descend to FL150) FL50 is not a very "likely" level, thereby providing an automatic check on the cleared level.
My second complaint about the US type phraseology is that it feels unwieldy to speak, but I do accept that this may be just because I only use it a couple of times a month.
Just my thoughts
G W-H