Miska,
If it is drums you're doing I recommend building 4 api 312's and 4 Neve's. You might be intending to have 8 of the same thing, but why not split it up? Both the Neve and API are phenomenal for drums, and you can mix them up for different color.
If you're really going to focus on drums (and other loud, rock sources), then I'd stick with a two-stage 1272-type arrangement for the Neve's instead of the 3-stage 1290. You'll never engage the 3rd stage on these sources as you won't need anything close to 55dB of gain (the point at which the 3rd stage becomes active in an old Neve).
One thing I will say to anyone considering my JC1272 variant -- I now suggest adding a second pot between the gain stages to act as a fader (the only pot on the schematic is a variable pad between the input transformer and the preamp stage). When the second pot is fully 'open', the circuit functions as normal. But trim this pot back a bit and you can then open up the pad a bit more and overdrive the preamp stage. This doesn't sound like distortion (at least not on transient signals like drums), but it does add a fair amount of bite and authority to the sound which is LOVERLY on rock drums.
Neve and API, you can't go wrong with these two for rock rhythm sections.
JC
PS - I think you were confusing the original Great River preamp and their current "NV" series. The original design (which is no longer made) was a much cleaner circuit than the NV series. The NV is based on the Neve topology but uses more modern components, both active and passive, along with Sowter transformers to yield a sound that is reminiscent of the old Neve, but clearer, faster, and more modern as well. The NV stuff is not a DIY.