Parasound Halo A-21 and 5250 vs. Sunfire TGA-7401?

Hey y'all.  I'm contemplating replacing the Halo (for my Magnepan 1.7's for 2 channel) and the 5250 (for the Martin Logan HT speakers) with the single 7401.  The extra power may not make a huge differnce for the 2 channel, but the current source for the planars has my interest piqued.  I am unfortunately not in a position to audition the options, since I live in a very rural area of the deep south.  I'm hoping someone out there has some experience with these pieces that can shed some light.  The A/B class and Downconverting of the Sunfire amp also has me wondering.  John Curl, vs. Bob Carver, hmmmmmm?