I own a Rotel 1075 amp and 1068 Preamp. I compared them directly to the Arcam AVR300 in my home. My friend owns the Arcam. We also listened to his new Arcam AVR350 the same night.
Associated gear: Proac Response 3.5 speakers, Acoustic Zen Satori Shotgun Speaker cables, Acoustic Zen Silver Reference II IC's, Rotel RDV1050 DVD/CD Player, Black Sand Silver Ref V and Violet Power Cords, FIM Stainless Roller Block Isolation Devices.
The Rotel was clearly more powerful than the Arcam 300. The Rotel Separates had more bass slam and punch in the low end. IC's were XLO Reference II. The Arcam mids and highs may have been slightly more neutral. "slightly".
Enter the Arcam AVR350. VERY impressive! It was clearly more refined sounding than my Rotel Separates. The Arcam AVR350 defined instruments more clearly in their own distinct space. Soundstaging and imaging were sweeter on the Arcam as well. Volume differences were almost indistingishable.
After comparing, I wouldn't hesitate to choose an Arcam AVR 350. But the 300 did not possess the same magic and I preferred the Rotel Separates in that contest.