I used to think half-rounds were only half of what was good about rounds or flats. Took me a while to start appreciating their uniqueness. They're certainly an acquired taste. Not for everyone.
I do agree the mid-forward character of the GHS Pressurewounds may not work equally well on certain basses. Also, they work better in certain band mixes than others. I do like them on my J than on my P for sure. My Yamaha with alnico humbuckers that tend to be darker and "polite" also seems to benefit from the Alloy 52's responsive nature.
I find this very interesting... "Hyper-rounds" or "uber-rounds" might be better terms for the Solo Bass 55 then?

I was suggesting earlier in this thread they might be a viable alternative to the now-discontinued La Bella Quarter Rounds, but apparently not according to your experience.