I believe that I am the most inconsistent factor in the use of my Tamron 150-600mm lens.
But, unlike the hordes before me who took a few shots (maybe), and then declared the lens "soft", I have been working to correct my behaviors and to understand how to use the lens.
And after literally thousands of shutter operations, most surrounding this lens, I'm finally getting a handle on my use with it.

It is capable of some incredibly sharp image captures. But as Regis has shown, it has an ability to have a very tight DOF (depth of field). Pinpointing one subject, while another mere inches further or shallower, will be OOF (out of focus)
I believe that factor is a delineating factor for the bad rap it got and reason it was declared as "soft".
People expected something out of the box, and when they didn't get instant gratification they Poo-Poo'd the Big Tammy.
I have 16080 operations on my camera purchased in July 2014. I typically can shoot hundreds and hundreds of shots at any given soccer game. And that, and my Humming Birds, were my reason for buying this lens on my rather limited retirement income. I had a need for range. ;)

To me, range depends on what your subject is and what you'd like to be contained in the frame. Mine is to capture a moment.
The flash of the male Humming Birds throat that is their main attractions to mate. I was lucky enough to actually observe a mating ritual unfold in my own back yard one summers afternoon. A male courting a female sitting on our service wire doing a dance. I guess he was successful, because the flew away together.
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