I have way too many SCSI emulators lol... SCSI2SD v5 and v6, BlueSCSI, RaSCSI... Right now BlueSCSI wise I'm using 2 BlueSCSI's that I assembled, one for an Apple IIgs (with a ProDOS and HFS volume on 2 separate IDs), and one for my MacSE (HFS volume).
Being able to take the SD card out, pop it into a computer/mac and have it recognized, and then mount or work with any of the image files on it in an emulator is amazing.
On SCSI2SD, if I wanted to take an already working SD from a retro Mac and work with it, I would have to either DD the card to the machine, work with it, and DD it back, or symlink to a block device and have Basilisk II interact with it (it works, but it's not easy or safe for most people to mess with that stuff, and it's certainly not convenient to do regularly).
If the new AzulSCSI has stability/support of SCSI2SD with ease of use of BlueSCSI, it will be a killer device to be completely honest. But I still personally hold the opinion that the SCSI2SD guys are not right for naming it like that, because people are already confusing it as an update to BlueSCSI, when in all actuality it's a ported and updated SCSI2SD that uses ~30 lines of BlueSCSI code and "feels" more like a BlueSCSI to use.