ArtPop has some better songs than Prism, but also some messier (Aura verses and Venus bridge like what was she thinking?).
But I'll go with ArtPop I still kinda listen to Applause, GUY and Sex Dreams.
I only listen to Spiritual these days from Prism.
Teenage Dream was flawless and I'm pissed Dressin' Up weren't on the album, it fits the whole TD theme with fantasising and everything. There was a concept, a theme, whereas with Prism, there wasn't a theme at all (said BB and other publications).
ARTPOP shouldn't have existed because like Gaga said, she's been doing ARTPOP since the beginning of her career and all the songs on ARTPOP are, a bunch of songs that don't fit together to form any theme. At least The Fame and The Fame Monster had a theme, of fame and love.
There are great songs like Gypsy, Venus' chorus, DWYW, MANiCURE, ARTPOP and Sexxx Dreams and good songs GUY, Applause, Fashion, MJH (IMO), but I feel it didn't work well together.
With Prism, I love Roar, Dark Horse, WOA, LL and I like Uncle, TIHWD and Birthday.
I love 13/15 songs on AP and I only like 6/14 (?) on Prism(not to mention it includes two of the worst song I've ever heard in my life, Bday and TIHWD, I still can't believe she released them as singles).
We all know Prism sold more but ARTPOP is the better album.