I've run the Apollos for a few years now, and they're excellent. Probably loafing on my 96dB/Watt Tannoys, but I do like it loud ;)
Dynamics as good as anything I've heard. Responds like crazy to tube rolling! All of the tube slots respond significantly, but especially those 12ax7 slots, which is great because you only need a pair! You can dial in your sound, or you can go crazy like I have with vintage tubes and change your flavor every couple of weeks.
I've had numerous flirtations with VAC gear now. I've owned the Renaissance III, which was run from its MC phono into my Apollos; ended up going back to the Hera II, though the VAC's excellent built-in phono was hard to give up.
More recently, I've been repeatedly impressed by a specially upgraded Sigma 160i, which runs 16K I believe. Man that's a nice sounding complete unit; it even drives Magico S5 with aplomb (actually it's quite a stunning combo).
The impression I get from VAC sound is that it is extensively (and skillfully) voiced to the VAC "house" sound. It's a beautiful sound; silky smooth and refined. But I've also noticed it doesn't respond to tube rolling like the Rogue gear. Because of the house sound, it's probably more important to audition, though it is a sound that's going to have wide appeal. The Rogue gear has a "house" sound too if you consider what you get from those awful EH small-signal tubes its "house" sound -- i.e. dry-ish and SS-ish for tubes -- but don't do that; get some decent tubes in there ASAP ;)
When I compared Ren III and Hera II directly in my system, the Rogue sounded more powerful as it stays flatter from the lower midrange through the bass and extends deeper. The midrange and treble is no-nonsense clear and neutral, but NOT cold nor analytical (it may sound a touch dry to those expecting more tube warmth). The VAC, by comparison, seemed to embellish a bit more...there was a slight midbass hump before its mild rolloff, the midrange was very beautiful, and the treble sparkled a touch more. In the beginning, I preferred the VAC. In the long run, I re-evaluated and happily went back to the Hera II, which fortunately did NOT sell here on audiogon when I posted it.
Though I've not heard the upgraded Sigma 160i in my own system, its sonics remind me of the Ren III, but done better. It's sounded fabulous on S5, S1, and Tannoy DC10A. If the VAC 300.1 takes that further with more power, it's going to be a hell of an amp.
And that brings us to the final consideration: cost. There's no question you get a lot more for your money with Rogue vs. other makers. Personally, the ever-rising VAC prices are a turnoff to me as a working-class audiophile. Other than the 160i, I have to balk at the current prices. I'm very happy with my Rogue stack. The Hera II is their best piece, and the Apollos are not far behind. I think the Ares sounds great too, but I wish they'd given it more of the all-out treatment of the Hera/Apollo.
