Yes, thank you for taking the time to do this comp! Maybe you'll start a trend, myself included. I see that others haven't been shy sharing their opinions, so I'll chime in too. Sometimes comps stall because the folks that actually did take the time to listen don't fire up the discussion in an effort to prevent spoilers and let others listen first. No sense in that.. everyone should download this and chime in.
First of all, I think it needs to be mentioned (and I don't see that it has been) that there may be an issue with preamp #1 and/or the combination of gear that made the file "song2preamp1.flac." There are several large clicks that sound exactly like a bad connector or jack. The output cable between preamp and recorder could also be the problem. It's definitely worth trying to reproduce, but luckily doesn't affect in the sonic comparison between these recordings
After taking into account that both samples for preamp #2 had the higher average RMS loudness, which can often account for preference, and ignoring the aforementioned issue, I prefer preamp #2. I thought it had a 'faster,' cleaner sound with much better HF. I felt that listening to the Fire on the Mountain chorus line was about the best way to get a clean comparison between the two sources and the detail on the cymbals, among other things, was much better to my ears going through preamp #2.