The problem I had with the Soundtraxx units was the same as what is being reported with the BLI ones, that is, I had trouble reading back the CVs I put in. This didn't happen all the time, but it'd do that every so often, and I'd have problems verifying if things were going right or not, since the NCE had routines it'd go through. When it didn't read, it'd ask for a value, but I don't know what that value is/was, so it was a real possibility I'd screw it up.
Now, I will say that I bought my NCE unit back in '00 or '01. I know that at one time, there was a discussion back then that the NCE unit needed to have the programming track voltage adjusted so the read errors wouldn't happen. I never had this done (procrastinated), but the Power Pax does the same thing. I do not know if the most recent NCE units have their voltages turned up to compensate.
This is a good thing, since on my Steamers, I have somebody do the installs and they set it up for me. I have one steamer that lost something, but I couldn't figure out what it was, because the NCE couldn't read that CV. With the booster, this shouldn't be a problem (haven't tried it yet). Also, I use Decoder Pro now, which will write the decoder values to a file, which simplifies the paperwork aspect immensely. It's a freeware program for the PC (or laptop), hooked to the serial port on the front of the NCE unit.