Obscuring clouds in external galaxies

Obscuring clouds are features to look for during visual observation of external galaxies. Although they often are very prominent in photographs, they can be very difficult to detect visually, since their surface brightness is not considerably less than the rest of the galaxy. In NGC891 the surface brightness of the equatorial dust lane is about 80% of the rest of the galaxy.

In which galaxies are the obscuring clouds easiest to detect? Here is my list in order of increasing difficulty based on observation with a 12.5-inch Newtonian:

1: M82
2: Andromeda galaxy
3: NGC3556 (M108)
4: NGC3628 (near M65/66)
5: M64 (Black eye)
6: NGC4565
7: M104 (Very low from my latitude)

I don't find the equatorial dust lane of NGC4565 to be easy to see, whereas it always seems obvious to me in NGC3628.
With 8 inches of aperture I generally find obscuring clouds considerably more difficult to observe. The only good ones were the three first ones on the list, and for the Andromeda galaxy, a dark sky was always crucial.

Other people's opinions? What can be seen in the small APOs or big Dobs?

Inge
The dust lanes of the galaxies you have mentioned (and others) are seen to great advantage in large Dobs. In my 40 inch f5 Swayze Dob the dust lanes of NGC 4565 and M104 look very much like they look in astrophotos. (Not like the Hubble heritage photo of the sombrero, like ground based astrophotos.) NGC 891 is one of my favorites, the dust lane in this ghostly galaxy is quite well seen.
In truth, these dust lanes are well seen in a 20 inch Dob as well.
Your post has reminded me to look back at NGC 3628 and study its' dust lane.
The dust lanes in Andromeda are prominent in the 40 inch, but minimum magnification there is about 167X so one cannot fit the entire galaxy into one field of view. For that reason, the view of M31's dust lanes in the 20 inch from a truly dark site like the Western US national parks may be more striking with respect to the dust lanes. If you want to hunt globular clusters in M31, the 40 inch is better.