SR-71 with the Shure E5c and Sensaphonics 2X-S.
Better than the SuperMacro v2 with 627 opamps (IMHO), the HeadRoom Coda (the MicroAmp will have to be a lot better to match it), the AE-1, or, just based on brief meet impressions, the Hornet.
It's a bit early, but I'm pretty sure the AE-1 and Shure E4c have a great synergy. I'll have to test against my other amps, but I'd be surprised if they match the Shure E4c as well as the AE-1 does.
All of these impressions were using just the iPod lineout as a source.
Best regards,
-Jason