McCormack DNA amp options....

Garfish is right. There is no question that a 0.5 sounds better than a 1.0. The Rev A+ with soft recovery diode is amazing. Maybe start with one and then add another to bi-amp, assumming your speakers are made for it. SMc will wire the inputs together so you can just use one cable per side, for a vertical bi-amp config (one amp per channel). With your high efficency speakers, I can't imagine you needing more than the 100 wpc @ 8 ohms, and you can easily go up to bi-amped 0.5s which Steve will tell you will sound much better than a single 1.0. In fact, I am about to send one of my 0.5s in to go up to A+, and then will bi-amp my Vandersteen 3Asigs. Steve does seem to be a fan of mono-blocking a pair of 0.5s, but then you are going to hurt re-sale or limit your ability to use them as stereo amps w/o re-converting them. But if you want a balanced configuration, monoblocks conversion of a pair costs the same as doing one stereo amp.

If the single stereo DNA.5 is satisfactory for sound level with your speakers, get all the SMc upgrades you can for the one amp except the mono conversion. Get a good power cord on it and enjoy. If it was the choice of getting two DNA.5 Rev A monos or a single DNA.5 Gold...go for the gold! You will know it's the upgrades that have improved the sound and can decide later to go Gold monos if you wanted more power. If you do both monos and upgrades at the same time you won't know which improved the sound more (if that's important).
Have you ever heard your speakers with 200w or 300w power?

Zach,
You have received somer very good advice, the best of which was to call Steve McCormack at SMc. He is very accessible and helpful. Let us know how you make out.

Labtec sez: "In particular, you can now get the Plitron toroid transformer for the .5 which significantly improves bass performance (among other things) and makes the .5 seem even more powerful."

Is this a fact? I notice the website says it availale only for the 1.0. This would eb good news if available and may well change my thinking strategy......

I spoke to Steve about 2 weeks regarding upgrading my .5 Rev A to a maxxed Rev A Gold. The Plitron toroid transformer is available for the .5. He has not updated the website to reflect the availability.