No direct experience with the Maggies, but having a sensitivity of 86 dB...I wouldn't think what you're proposing will work, either option. I once drove a 90dB set of speakers with 60 watts of (KT88) tube power. Sounded..wonderful..but volume-wise..I could only get to moderately (low-ish) volume.
By all means pursue the Maggies, but you'll need a tube preamp and some real power. My current system, due to change completely in a couple months, runs a tube pre into a McCormack DNA1 power amp into 86dB speakers. It totally works. I've enjoyed this system for 10+ years..no complaints.