I have their Motown DI, it’s great. It’s not the definitive Motown tone people search for, but it’s a step towards it. Way too expensive though.
For what it’s worth I don’t think Motown bass tone is that difficult to work out. Booze, P-bass, rosewood board, dead flats, high action, tone down a bit, pluck in front of the pickup, straight in to a D.I., then a bit of tape saturation, or if you want it to be a bit more legit, actually record to old tape, then you’ll get all the dusty artefacts too. There’s not much more to it than that. The breakup you hear is the signal clipping, it goes way past the threshold on the lower notes in some places.
The transformers, tubes etc that people obsess over when trying to recreate that sound have far less to do with the fundamental character of that tone than we think, and they will only really make a difference to engineers listening on super high end monitors. They’re just the cherry on top. You can get to 99% of the Motown tone even with a fairly basic setup. Don’t forget the booze though.