I like the sound of Arcam, just never thought of them seriously as a HT vendor.
Perhaps others can enlighten me, but to my memory many stereo companies have made half-hearted attempts to get into HT processing and AVRs but few have stuck it out or really developed a broad portfolio of products that makes me feel really comfortable about their HT line.
For instance, if Audio Research suddenly developed a HT processor.... just one... I probably would avoid it thinking they don't have the engineering chops to keep it up to date.
I haven't kept up with Arcam in forever though, so not sure how much of this applies.