Hey Mardoo, thanks for your comments.
With my limited experience, i'd probably agree with you that the smoother impact of the flowers blend well into the malty elements straight away. Whereas the pellets seems to provide more hoppy oomph, but can be a little harsher (initially).
However,
Mardoo said:
...I'm not inclined to cube hop with leaf hops after my last couple experiences. It seems the vegetal element of the hops comes through much more easily when cube hopping with leaf. This could be fine for something that you're going to age at least a couple months, as it definitely fades. However, too much hop presence faded in the last IPA I did, before the vegetal aspect got to a level I felt it didn't stand out.
...
I'm not sure i'd agree with this (for my tastes).
It could be from a very limited experience with flowers, but i'd be tempted to say the opposite - that when cube hopping the flowers seem smoother to me with less vegetal by-product than pellets. The way i'd see it is that the vegetal flavour comes from all the "other" cell components/compounds in the hops material/tissue, and these are more "available" to dissolve into the wort if the hops have been shredded-up like in pellet form.
Another aspect to this theory is that the hops that have a reputation for being harsh (e.g.: Galaxy) are strains that have higher levels of these "other" compounds, such as tannins. So it should follow that for hops that are reputed to be less harsh there should be less difference between flowers & pellets, whereas something like Galaxy might show a greater difference between flowers and pellets (when used in boil, cube or dry).
I could be heavily biased in wanting to believe all this, though, in that the first few times i used flowers in the boil i found large amounts of the lupulin glands still in the flowers and on crushing them i got a huge aroma from them. I took it to mean this was lost potential i was missing out on. This occurred even after a 90min boil. So as a result of this, i decided cube hopping might provide a better chance of getting the most out of these flowers (due to extended high temp exposure plus generally a very long time sitting in the cube overall), combined with crushing the flowers a little prior to using them.
So given i already started down that path, maybe it has been my wishful thinking that gives me the impression the flowers in the cube are smoother.
Anyway, interesting to see how this comparison between flowers & pellets expands as we get greater exposure to flowers via the likes of Belgrave Brewer.