Hi Paul,
Welcome to the forum and hell yes what an absolute bargain. The CHB-1 is one of my favourite basses and I'd love to have one, especially at that price!
If we assume that active controls go from +10 to -10, then my main basses are as follows
Shuker: bass +2, mids 0, treble 0
Sire V7: bass +3, mids 0, treble +1
Ska bass: bass +4, treble -3
Thunder 1A: bass +2, treble +1, pickup in series mode
I would, if it makes the right sound (see above re: my Schaller). If you get one, drop it in and then decide against it, or change it further down the line, you can sell it on probably for what you paid for it (assuming you get it used).
I had cheapáss J pickups in my similarly cheapáss ska bass, they were errrrrrm okaaay I suppose... found I was using only the neck one, then remembered that I had a hot Schaller J neck one in the spares box so I fitted that. It was like the difference between very chalky chalk and extremely cheesy cheese. You would never have dreamed that they were both basically magnets with bits of wire wrapped round them. And I don't just mean in terms of loudness (the stock one was 6-7K, the Schaller is 13), the tone was different too. The stock one sounded like a normal J, but the Schaller is more like a slightly compressed P but really really aggressive. Not necessarily better but different. Perfect for my needs. So my longwinded answer to the OP is hell yes it makes a difference.
Apologies, it turns out the one I had was the plain Trakmaster, not the Pro.
This is a screen grab of the manual section of the Trakmaster. Apologies for the poor quality.
My current one is 4U... I could probably get away with 3, but the amp is a Shuttle so this means the case is still pretty light. I had a well-loaded 6U at one time, now that sucker was heavy!
I also had a Focusrite Platinum Trakmaster Pro for a while. Beautifully pure-sounding, lovely EQ and still the best compressor I've ever used. Channel strips are brilliant if you want an uncoloured sound.