My number one pet peeve about speaker manufacturers is the lack of driver controls on multi-way speakers. Do they really think the levels they chose are optimal for all listener preferences, all rooms, all locations of the speaker, all upstream equipment choices? I know that some manufacturers hated controls not just for the extra cost of an L-Pad, but also because it is too easy for owners to mess up (the optimal choice often involves making incredibly small changes, and change in one control often also requires changes in the control of another driver. Still, I require such control. It might well be the case that Volti's way of allowing control, but not making it easy, is a good choice.
I too like the Avantguard speakers but was trouble by the lack of bass integration. Voltis are much better in that regard, though it is a bit of an issue with their speakers too.