Been using a 5GS for years to give me a similar feel on medium bore to the 5G I use with my 88H. Can't complain really, its a deeper cup, free blowing, you work a bit harder in upper register, but in return your large bore playing is pretty much unaffected. It doesn't give you that ultra-clean lead trombone sound, but a fuller, and better in my opinion, sort of 2nd to lead trombone sound. Was suggested to me by Phil Parkers.. need say no more.
This purchase was a replacement for a friend based on my experience.