Sony FE 600mm F4 GM OSS

I shoot birds in low-light forests and the XA lens really pulls out feather details I couldn't get before with my old tele. It's noticeably lighter than I expected for a 600mm, which makes a big difference when I'm hiking in and out of spots.

Shot a whole afternoon of birds in flight and my shoulder barely felt it—the weight balance really makes a difference. The bokeh from that XA element is ridiculously smooth, even against messy backgrounds.

The autofocus is just incredible; it locks onto birds in flight faster than any lens I've used. Even fully extended, the balance makes handheld shooting possible for hours without fatigue. That XA element really delivers edge-to-edge sharpness wide open.