I actually came in here lamenting this, because I feel like it's comparing Kate Upton to Paul Williams, or Frank Sinatra to Anthony Keidis.
I know for me, I love both of them, but Ritchie Blackmore is my favorite musician of all time, ever, and while there is some hit or miss stuff in the catalog - and Deep Purple could learn a thing or two from Rush in terms of "band relationships" and "how to respect your partners" - I'm a Purple man.
Interesting, because "Hemispheres" is in my top five albums of all time, and Deep Purple probably doesn't have ONE album that reaches that level, but Purple has about 6 or 7 that are just a hair below that, and so...
Purple.