My particular take on trim tabs may be different than others but here goes.
We originally installed a Permatrim on our Suzuki 70hp engine and loved it. We repowered after the 1st season to a Suzuki DF90 hp without the Permatrim but with Bennett M120 Trim Tabs. IMHO, the trim tabs work ok for getting the bow down and work very well for lateral trim. We were just used to the instant response and adjustment that the Permatrim provides for adjusting the bow trim.
So, we added the Permatrim on the new engine and our preference for the Permatrim was confirmed. We still use the trim tabs to adjust the ballast but prefer to use the Permatrim for trimming the bow (and stern). In any case, whether it be TT's or a PT, having them on the boat really makes a difference when running through choppy water and serves to minimize pounding. Therefore, I would rather have TT's (or a PT) on a CD22 than not.
Hope this helps. And as noted above YMMV.
Peter
C-Dancer