I have the "baby version" of the match you are proposing, in my case the ARC LS-17 paired with ARC's 150.2. I think they work very well together driving my Maggies. However, I'm sure you are aware that the 300.2 is one of ARC's first class D amplifiers, and there is a wide range of opinions about them. Based on my own experience I think the 150.2 and 300.2 sound fine (and in fact the Absolute Sound reviewer bought his review sample of the 300.2), but they were never meant to compete with ARC's own Reference Series tube amps, such as the Ref 110 (i.e. ARC themselves would maintain that the Ref series amps were of higher musical quality). The synergy is there, but you should listen for yourself.
