I owned the Transit B for a bit. I found the compression and drive useless. I used it in a IEM only direct situation and found it also had a lot of noise. I think it may be the power supply creating the noise but I can't say for sure as I ended up not keeping it long enough to find out. The Trace tone is good though and I ended up buying an ELF and have used it a few times direct as a DI and it was quiet and sounded pretty good. The always on compression can be distracting at times on the ELF.
I also currently own the Spectradrive and am currently using it direct with IEM. I like the tone of the unit and do use the Captain East compression setting on a low level. I have not found a use for any of the drive toneprints as I just can't get anything that sounds good direct to the board. The DI is fairly good though. But having said that, I'm on the hunt for a better sounding preamp / di for direct use....