What LoVendoR is doing and what Silent Siren does are just two different things. Silent Siren's sound is really idol pop in a more-or-less rock-group format, but it's pretty clear that from the start, LoVendoR has aimed at being a genuine rock group. It's just a very different tradition. (And I purposefully used the word "tradition," because by now, both idol pop and the kind of classic rock sound that LoVendoR has
are both well-established traditions.)
I'm glad that LoVendoR is taking the rock group path, rather than the idol pop/sort-of-rock-group path, in part because I want to see them break out of the idol pop category (which encompasses pretty much everything else in H!P), but mostly because I actually prefer the girl rock-group sound to most idol pop.
But these are
all matters of personal taste. The bottom line is that LoVendoR has, for better or worse, placed itself in the rock group tradition, rather than the idol pop tradition.
And I'm looking forward to their 45-minute version of Stairway to Heaven.
If madness made us strong, we would all be invincible.