Part of me thinks it's a no brainer to go w. the Primus 150s w. the Topping amp. It's got a DAC and headphone amp included, but I'm also torn between these and the A2s because of their small footprint. My office is pretty small and I can't play anything too loud. These will only be used for music, mainly progressive rock. Any advice is greatly appreciated.
I'd stick with the Infinity Primus unless you can find a way to listen to those other speakers. The A2s are certainly not better with their tiny drivers.
I'd recommend considering a TA2021 t-amp over the TA2024 in the VX1 just because they have a little more power. Topping makes one. This Indeed is excellent as well. Then you could add a better sound card to your computer for a better DAC and headphone capability.