My soprano is a Schilke with lightweight ("Beryllium" - although they're not really beryllium at all) bell. I currently use a Schilke 12B4 mouthpiece, but I'm starting to think about switching to something a bit bigger. I also use a Schilke Bb cornet.
I've never experienced any real problems with it being more easily damaged; you can damage any instrument bell fairly easily if you're careless. I have Schilke Bb & C trumpets with standard and lightweight tuning-bells, and I think the potential for damage is a little greater there, because of the reduced bracing. The real problem is when you switch to the lightweight bell on the Bb, it's usually for the purpose of Bigband or show playing, ramming lots of mutes in quickly!
I've never had a problem on my soprano with the G# that has been mentioned (although that note is a bit flat on the 'C' trumpet); the bigger problem for me has always been the low F (bottom space) being flat. The band has a Yamaha which is much worse on that note.
I've only played a Courtois very briefly; my immediate impression was that it seemed to "close down" a bit from top 'A' upwards; the Schilke always feels more "open" up there. For me, the main advantage of the lightweight bell is that the instrument "speaks" more easily at low volumes, so high/quiet bits are less "nervy". The lightweight bell also helps get that "laser beam" screaming sound that rips right through the band, but of course musical soprano players wouldn't consider that important! :wink:
However, as has been previously mentioned, it's all down to personal preference, and what works for you. I don't believe there is a "better" soprano than the Schilke, but, as you can probably tell from my instrument collection, I might be a bit biased!
Regards,
Gareth