[GeneV]

my feeling is that the 50-135 is just not long enough. Once I want longer than a 40mm or 50mm, I want REACH. I'd get the 70-200 and a 1.4 to take you further

Reach is addictive. Quite a bit of the time I am using the DA*300 + HD 1.4x, I am thinking the same thing. When I am using 500mm +1.4x L for birds, I have sometimes thought it is too short. For me, the 50-135 is to fill the gap when the DA* 300 is too much. I can crop my way out of too short (to some extent) but too long is not really curable.