At a B-mod level I'd probably take the DNA-225 as Steve McCormack has said that for the most part he's incorporated that level of parts in the new amps, although my choice would change if I found a serious bargain on a DNA-1 Rev. B(same holds for DNA-125 vs. DNA-0.5 Rev. B). I believe the A Revisions take the amps a bit higher than possible in the new models(due to practical cost/price constraints), so I'd probably take a DNA-1 Rev. A over a 225 and a 0.5 Rev. A over a 125 assuming prices aren't wildly different. If I didn't need the power I'd probably take a DNA-0.5 Rev. A over a 225 as well, as I'd take the added refinement and transparency over the additional watts. You can go to smcaudio.com to read about what the various upgrade paths offer. I own a DNA-0.5 Rev. A and am extrememly happy with it, but I don't think you can go wrong with any of McCormack's amps. Best of luck.
Tim
