A few months ago I reconfigured my HW50, putting it back in the OEM stock, and replacing the target scope with a fairly small 3-9. I've had few offhand sessions with my HW50 in the last couple months since the reconfiguration, and it's been on my mind lately.
Current state...

In my opinion, the hold sensitivity of the 50s is very low compared to the 77k, making the 50s much easier to shoot. I also like the lighter weight and more compact size of the 50s over some of the larger springers like the 77/97, TX200, etc.
I always hear about how hard the model HW50s is to cock, I haven't ever thought it was hard to cock. Some say the articulated cocking arm increases the cocking effort, and it might, but I think the articulated cocking arm is what makes the gun special. It doesn't have the typical stock fork screws at 180 degrees to each other like you see on most break-barrels. For stock fixing, It just has one big lug screw on the bottom of the forearm and a smaller screw in the trigger guard. Something about that configuration makes the gun not require loktite, nor does it develop a wandering poi problem like I've seen with typical stock screws through the fork. My guess is that the thin wood on a break barrel stock fork that the screws would regularly go through, are subject to swelling and flexing through humidity/temp changes, which equates to shifting poi and screws that won't stay tight.
As for why I think it is less hold sensitive...
When I was on a serious springer kick I did a ton of research and talked to guys a lot smarter than me when it comes to springers. I don't remember the exact values but the stroke length of the 77/97/95/98 are all about the same, whereas the stroke length of the 50s is shorter than the others I just listed. The 26mm comp tube is shared across the 50/97/77/95/98 but the shorter stroke length of the 50 means the pellet is gone faster. We're talking milliseconds here but the 50 is simply easier to shoot and isn't as picky about how it is held.
It seems like I remember the 50 stroke length was about 10-12 mm longer than a 30 and about 15mm shorter than the 77/97/95/98. That, obviously, puts it right in the middle, which allows it to generate enough energy to be useful but not enough for it to get hold sensitive and jumpy (unless you really space up the spring.)
I tested all this out by putting a short stroke piston nose cap from Tinbum in a 77k at one point. It greatly reduced the hold sensitivity and only cost me about 0.5fpe (with a couple washers to space up the spring again). BUT, the 77k was still heavier and less nimble than the 50, and the 50 was still slightly less hold sensitive.
If I ever end up with a 77/97/98/95 again, it will get a short stroke nose cap. In the meantime, I'm pretty happy with my 50s and have no intentions of trying out the longer piston stroke/heavier/bigger family of 26mm comp tube HWs again.
For further context, I even tried out two specimens of the new version of the FWB Sport that goes for $500-$700. The Sport had/has nothing on the 50s and I no longer have a FWB Sport.
After cycling through nearly all the high-end springer options, the HW50s is one of only three springers that earned a long-term spot at my house. The other two being FWB300 variants.
Current state...

In my opinion, the hold sensitivity of the 50s is very low compared to the 77k, making the 50s much easier to shoot. I also like the lighter weight and more compact size of the 50s over some of the larger springers like the 77/97, TX200, etc.
I always hear about how hard the model HW50s is to cock, I haven't ever thought it was hard to cock. Some say the articulated cocking arm increases the cocking effort, and it might, but I think the articulated cocking arm is what makes the gun special. It doesn't have the typical stock fork screws at 180 degrees to each other like you see on most break-barrels. For stock fixing, It just has one big lug screw on the bottom of the forearm and a smaller screw in the trigger guard. Something about that configuration makes the gun not require loktite, nor does it develop a wandering poi problem like I've seen with typical stock screws through the fork. My guess is that the thin wood on a break barrel stock fork that the screws would regularly go through, are subject to swelling and flexing through humidity/temp changes, which equates to shifting poi and screws that won't stay tight.
As for why I think it is less hold sensitive...
When I was on a serious springer kick I did a ton of research and talked to guys a lot smarter than me when it comes to springers. I don't remember the exact values but the stroke length of the 77/97/95/98 are all about the same, whereas the stroke length of the 50s is shorter than the others I just listed. The 26mm comp tube is shared across the 50/97/77/95/98 but the shorter stroke length of the 50 means the pellet is gone faster. We're talking milliseconds here but the 50 is simply easier to shoot and isn't as picky about how it is held.
It seems like I remember the 50 stroke length was about 10-12 mm longer than a 30 and about 15mm shorter than the 77/97/95/98. That, obviously, puts it right in the middle, which allows it to generate enough energy to be useful but not enough for it to get hold sensitive and jumpy (unless you really space up the spring.)
I tested all this out by putting a short stroke piston nose cap from Tinbum in a 77k at one point. It greatly reduced the hold sensitivity and only cost me about 0.5fpe (with a couple washers to space up the spring again). BUT, the 77k was still heavier and less nimble than the 50, and the 50 was still slightly less hold sensitive.
If I ever end up with a 77/97/98/95 again, it will get a short stroke nose cap. In the meantime, I'm pretty happy with my 50s and have no intentions of trying out the longer piston stroke/heavier/bigger family of 26mm comp tube HWs again.
For further context, I even tried out two specimens of the new version of the FWB Sport that goes for $500-$700. The Sport had/has nothing on the 50s and I no longer have a FWB Sport.
After cycling through nearly all the high-end springer options, the HW50s is one of only three springers that earned a long-term spot at my house. The other two being FWB300 variants.