8vm - A personal favorite. Title track. Sort-of concept album, closes the meta-album run.
SC - A flawed album, but fun.
BC&SL - I liked this one a lot, flawed still, but this album packs a punch.
ADTOE - One of the band's best albums.
DT12 - The worst of the band's albums.
TA - Still digesting, but while it's better than DT12, I don't feel like listening to this much.
8vm-ADTOE have many songs I'll listen to individually. Nothing on DT12 or TA has really excited me. The orchestral section in Illumination Theory is beautiful, but the entire composition is disjointed. There's cool moments throughout the 2 albums, but IMO DT suffer from an arrangement problem, something MP is good at. ADTOE may have been a last hurrah of sorts, being the album was a "back to our roots" kind of album. Moving forward, I haven't been too pleased with the new albums. BC&SL and ADTOE were the last albums were I was pumped hearing a new DT album, and continue to enjoy those and every Portnoy album, while occasionally dipping into the newer stuff to see if things have changed. So far they have not.
So TL;DR - I prefer the last few MP albums over the first 3 MM albums, flawed as they are. ADTOE is the best album of the six, but DT12 really brings it down for me. TA is 'ok' so far, I don't want to say I don't like it because I'm still digesting it, but there isn't a whole going on that makes me think "Man, I gotta listen to that again!"