They are both good guns.

The HW95 is heavier and more expensive and puts out a bit more power.

The HW50-S is a 6 lb rifle that puts out just under 12 ftlbs (twice what the JW30/R7s do)
The HW95 is the same gun as the Beeman R9.. They weight about 7.5 lbs and put out 15 ft lbs..

Both can be a bit "buzzy" out of the box but NOTHING like cheap magnum Chinese specials ..There is also a bit of luck of the draw between guns as they do vary slightly. All of them smooth out with use .

If I was getting a .177 and wanted a light gun, I would get the HW50.
If I did not mind the extra weight and /or wanted a .22 - I would get the HW95.

I think due to the cocking linkage, the HW95 is a bit easier to cock in relation to its power level. The HW50S is quite a bit of power crammed into a small package.