The reason for that is because unless the person(s) doing the review had the exact same audio equipment as I have , they wouldn't be hearing the same as I do.
Onto isolation and leakage of the LCD-XC, some find them to be good at both, whereas others don't, and I'm one of the don'ts, and this is with the LCD-XC's original headband.
When it comes to testing for isolation, IMO the only way to do that is with no music playing, that way there'd be no interference with outside noise, and to me when wearing the LCD-XC with no music playing, it's very easy to hear outside noise, however, when doing the same thing with my UM Miracles, I can hear a very faint noise, and with music playing I can hear nothing from the outside, whereas with the LCD-XC the only time I can't hear outside noise is when the music is being listened to loudly.
When it comes to SQ of the LCD-XC's, to me they are not far behind my SR-009's, and with some of the songs in my collection, I find the LCD-XC's sound better than the 009's.
P.S. The amps I have and use with my LCD-XC and 009 are GS-Xmk2 and BHSE .
I'm also very happy with the LCD-XC when using my Pico Slim.