I use ProAc Response 2.5s, but don't have them set up exactly to ProAc spec. I like being able to slightly see the insides of the cabinets when they're facing me, rather than pointed straight at me. And I sit in a chair with castors so I can roll back and forth depending on if I want a closer, more intimate listen or further back to simulate being further into the audience. By in large, my set up is an equilateral triangle and is varied by my seating choice.
In general, I would start with the manufacturer's recommended set up, then adjust from there according to your taste.
In general, I would start with the manufacturer's recommended set up, then adjust from there according to your taste.