Hey Dan,
i've tested both: Fab and H-Delay. Yes, you are right. If you listen very closely you can hear the continuous filtering. It is not as obvious as in Timeless 2, but i think it's because of the lo-fi switch that attenuates some hi frequencies that i carved out. But in the end, it's doing what i want. I find Timeless a little more flexible at the end so it's my choice for buying. After all it's also a little bit cheaper ;-). Thanks for the pointing me in the right direction.
Edit:
Ok, the possibility to do a little bit of resonance peaking in timeless really brings out the effect even more. One more point for Timeless 2.
Axel