I own the Primare I30 and CD31 with Sonus Faber Cremona Auditors. I auditioned the Primare I21 and CD21 with SF Concertos at the dealer. There isn't a huge leap between the 21 and 31 series, so if you want to have the "Primare" sound but save a few pennies, you won't miss TOO much by going to the 21. Primare has a nice sound, but can be edgy sometimes. I find the sound to be slightly laid back but with a bit of grain. Odd I know, but that's the presentation I hear. My Shunyata PCs take some the edge away, but sound could be "cleaner". I'm being picky, but for the price of the 21 series, Primare is a great deal, the 31 is less so, to my ears.
HTH.
HTH.