Some of the SRX sounds such as the brass and string boards were absolutely excellent in the early 2000s, they were used by Madonna‘s band on stage etc.
Unfortunately, Roland abandoned new sampling sessions. As I know from members of a German forum, the original sampling data of many SRX sounds used to be sold in much better quality and larger sample sizes on CD-ROMs under the Spectrasonic label (Eric Persing) in the late 1990s, so technically one could make them available in larger sample sizes for the new Fantom. I guess it‘s a license issue they don‘t do it.