Oh w
Oh wow, I just looked up the Velaton Dapper. That looks like a nice unit for quite a bit cheaper. I’ll have to explore that further
This may help then:
I have both the Tech 21 Bass Fly Rig V1 and the Valeton Dapper Bass. The only thing I wish the Tech 21 had is the clean Octave effect present on the Valeton (kinda a Boss OC-2 copy and notably glitchy).
I previously had the Tech 21 Bass Fly Rig V2 as well, but I traded it for other gear when the opportunity arose as I preferred the V1 for the Tone knob (2khz-3khz) on the compressor section, and I preferred lowering the Character knob in the Sansamp section to dial in warmth when needed in addition to the Mid knob fixed at 1khz. I never used the post-sansamp effects loop on the V2 personally, and I didn't care for the higher-driven sounds I got swapping between Channel 1/2 on the V2 since I only had one set of EQ controls for both channels. I much prefer having my YYZ Sansamp pedal with its own EQ for Dist/OD tones, despite it needing to be placed in front of my V1 Fly Rig.
I don't consider the V1 superior nor inferior to the V2 in any way whatsoever, it's merely personal-use preferences. IMO, everything other than the clean OC-2 tone on the Valeton generally sounds/works better on the Tech 21 units, including the tuner.
The Chorus on the Valeton produces a modulation effect that is just too much above 1-2 o'clock, while the chorus on Tech 21 is a Detune chorus effect usable at any setting, both are good. It's hard to describe, but there's a kind of ringing-swirl-like effect present in the Chorus section on the Valeton, not really a flanger-like effect, but in a pinch it sounds better for, "Tool - Forty Six & 2", than the Detune chorus on the Tech 21 if that helps.
The envelope filter effect on the Tech 21 sounds good but keep in mind it isn't very flexible like a dedicated pedal would be with sensitivity controls, while the Dirty Q filter section on the Valeton is like an EHX Bassballs pedal with hypersensitivity at all times. So unless you're playing, "RHCP - Sir Psycho Sexy", every gig, you're likely going to find the envelope filter on the Tech 21 unit to be more useful in general.
You likely won't enjoy the Tech 21 Octave or Fuzz effects on their own, but combined together you can clean up the fizz and passably balance the tone with the Mix knob, plus you can crank the Q knob to turn it into a synth-like effect. Not really practical to me overall, although it works fine if you love dialing in various synth tones I suppose. I only every really use these effects together if I'm playing, "Mogwai - Wizard Motor", or, "Jamiroquai - Deeper Underground", once in a blue moon. 99% of the time my Octafilter section gets used as an Ok-sounding envelope filter, just remember that it isn't very tweakable overall compared to dedicated filter pedals out there.
The compressor is mostly the same on both the Valeton and Tech 21 units, the attack is too aggressive on both but they're overall fine to me. Just note that the Compressor on the Valeton produces additional volume, even with the gain knob on the compressor section all the way down, so you can't maintain unity gain while swapping between Compressor on/off. I've found that it needs to stay on at all times.
Note that the stomp switches are silent on the Tech 21 units while playing, but you'll hear a small pop through your speakers using the Valeton unit if you stomp on a switch while you're playing. This aspect drives me nuts sometimes but you be the judge. My Valeton lives on as a satisfactory backup that I'm happy to have with me at all times.
You can hear the 'pop' here in this member's demo when he stomps the effect while playing: