You know the old saying Felix, vertical antennae radiate equally poorly in all directions.
If one has a properly installed vertical antenna with the needed RF counterpoise system or one of the offset fed vertical antennae, they will work OK in certain instances.
The take of angle of the vertical antenna makes it a good candidate for DX.
I use both a Hy-Gain 18AVT and a Hy-Gain DX-77. The DX-77 supplies its own RF counterpoise and works better than one might expect.
However, as you know there is no substitute for full sized, resonant antennae and the loop antenna is one that I enjoy using.