Yea I noticed the same thing, passives seem more agressive on the low end and smoother on the top, from my experience it is hard to get an active to sing smooth like the passives do up on the 15th-20th frets on d and g string unless you do some serious tweaking on amp or bass settings, actives seems a bit twangy and you hear more of the string rather than a smooth note, but like I said thats my experience, that doesn't mean it will be like that for everybody. I do like how smooth and boomy the actives can be on the low end though. I'm a bit indecisive myself between the two but they both got their advantages.
The huge difference for me I can notice between the two is how modern the actives sound and how old school the passives sound when blended in with the rest of the band, but I believe that either can fit into any situation and there shouldn't be any perameters or rules about which should go with what, imho that would be like comparing using fingers or a pick and saying one is better than the other. I think any of them is great and it is a matter of what you as a bass player can do with it.
