I'm contemplating the acquisition of volumes IV-VIII of the Arduin Grimoire series and would like some advice from those who own them: are they worth getting? I have the original three volumes and, while I'd never use everything in them, I've found them quite inspiring and often cherrypick good ideas/mechanics from them. Do the later volumes provide the same "bang for the buck?" If the general consensus is that they do, I'll likely pick them up, since I've been curious about them for some time.
Thanks in advance.