I currently running a pair of Jeff Rowland Model 6 monoblock amps Steve. Plenty of power, and good bass control. I've long been a fan of the tube preamp/SS amp combo, and currently mate a ARC Ref 3 with the Rowlands. It's quite a nice match. I've also previously used a BAT VK-51SE/ VK-600SE combo with much success with the Parsifal's too. I wouldn't say the Rowland's are better, but I do prefer the soundstage created by monoblocks. They also cost a bit less than the BAT VK-600SE. I do like the ARC Ref 3 better than the BAT VK-51SE though.
I wish I could afford to try a darTZeel, but probably not this decade. :)
The Parsifal's are great speakers, it's hard for them not to sound good. I have one friend who swears that they still sounded best when I had a VAC Avatar Super integrated amp driving them. Though it did have plenty of midrange magic, I prefer the slam and authority of SS amps driving them, as it seems you may as well.
Cheers,
John