I use on all the time and it is a big part of my sound. There are a few things to keep in mind in working with them, though. First, a little tweak goes a long way on them so, adjust settings gradually to get the best effect.
Second, the device is a preamp as well as a DI, so if you are going to send that to an amp, watch out for sending too hot a signal to the amp. The instructions speak of "unity gain", which is essentially the point where the volume leve of your instrument is the same whether or not the Bass Driver is engaged. Start from unity gain so you don't end up blowing speakers, etc.
For recording, I use the device to eq my signal going to the amp (which is recorded with a mic) and then run the parallel output from teh Bass Driver to the board, so I get a really driving effected signal going through my amp along with a cleaner signal going straight to the board. Works well for me, but I have a bit of a driven sound.
Finally, take some time to explore the device and read the instructions. At first I hated the thing but once I learned how to dial in the tone I like, the Bass Driver is a permanent part of my set up.