I think that it may be hard to match the synergy of ProAc speakers with ARC pre and power, but for my office system, I wanted a very conservative, classy look, and I ended up with all Arcam FMJ components (FMJ A22 integrated, FMJ CD23T player, and FMJ T21 tuner) to drive my Tablette Reference 8 Signatures. Your 2.5's may require more power. I don't have experience with them. But as far as making for a nice SS amp match-up with ProAc's, I am very happy with the sound of the Arcam equipment. Of course, I still prefer the sound of ARC with ProAc's.
Tom.
Tom.