The HS50 is incomparably better. Obviously the zoom (x30 has increased from x42) Without a "price" to pay in terms of speed ("F") of the lens !!!
The layout problem sometimes to the point "delicate" impossible with the HS10 has disappeared. Almost never difficulties.
The screen swivel in all senses is beautiful with its 4 times more pixels than the HS10.
The Li-Ion battery are excellent. The problem with little warning time before the "dry down" that existed with the HS10 still exists ... The indicator goes from 3 bars (= full) has 2 bars after hundreds of photos, but the fault is very soon after ...
I selected from the canon, nikon and big zoom Fuji because of its better brightness, and lower prices.
The pleasant surprise is the quality of the photos. Incomparable with the HS10, so the internal software has been improved. Very few artifacts (electronic impurities) and colors "on Fuji".
The EXR is not essential and the stage, although properly functioning are of little use. The Advanced mode provides some additional tools, but all are not yet Successful.
Conclusion: An extraordinary camera for the photographer (more) advanced beginner.