Free The Tone Black Vehicle. Like the DCX Bass, it has that organic, natural, and not overly compressed feel. The Black Vehicle uses an IC design to simulate tube saturation and it does an excellent job. It is the most tubey of all non-tube drives I've played. If you are familiar with the Fairfield Circuitry Barbershop, the Spaceman Saturn VI, or the Origin Effects DCX Bass (I know you know that one) it's like those only with a more articulate low end thanks to its mix control. You can use that to dial in the balance of your clean tone and overdriven tone. The DCX Bass as a fatter, warmer low end than the Black Vehicle which is also nice in its own way. I think that comes from the vintage studio console tone Origin Effects was aiming for. So think something like:
Black Vehicle = tube amp saturation
DCX Bass = studio console overdrive
Both are great, and they are more similar than not (compared to other the full offerings of overdrive available), but they are definitely each doing their own thing.
Like the DCX Bass, the Black Vehicle has a nice sizzle to its trebles so if you need something with a little more high-end bite, this might be a solid option. (And if you need a darker tone, that sizzle can be EQed out with the treble pot, like the adaptive voicing toggle on the DCX Bass.) And also like the DCX Bass, it has a 2-band EQ instead of a tone pot so you have that added flexibility. But while the DCX Bass is voiced to keep the drive in the upper register (I'm sure you've notice it doesn't clip the full spectrum), the Black Vehicle clips more (but not all) of the spectrum so its drive tone is a thicker than the DCX Bass's. The gain and mix knobs, of course, let you control how heavy that drive tone gets. At higher gain settings I find the Black Vehicle too farty so I want to stress this is a true overdrive. If you are looking for fuzz, then this is not the pedal for you.
The coolest and most unique feature of the Black Vehicle is its secondary stompswitch: it has a boost that you can set to be pre- or post- the drive stage so it can be a gain boost or volume boost. I set mine to be a low-gain overdrive (just past edge-of-breakup) and then have the boost turn it into a medium-gain overdrive for intensifying a bridge or second chorus. The secondary stompswitch does mean this in enclosed in a 1590BB (turned the long way) rather than a 125B so it will take up a bit more space on a board; at the same time, that boost option gives you two gain-stages in one so it might actually save you space by removing the need for a separate boost or second dirt pedal.
Ultimately, the DCX Bass and Black Vehicle are both excellent pedals and I'd be happy with either on my board. They are a little different in their features and voices, but I don't think one is vastly superior. I love the responsiveness and tubeyness of the Black Vehicle, but the warm low-end and 125B enclosure of the DCX Bass are also great. Although I like the clipping of the Black Vehicle more than that of DCX Bass, I could easily see someone else preferring the opposite. There's no right or wrong here. Just different options of excellent.