Gymnocalyciums are real gems of the cactus world: easy to grow, easy to get to flower, and they make very nice specimens in a relatively short while.
The variety name is no longer accepted by botanists. It's simply G. pflantzii. I just throw in that nice long variety name as a teaser. And it's fun.
For those of you in the Portland, Oregon area...hold those dates: July 18, 19 & 20. Those are the dates for the Oregon Cactus & Succulent Society Summer Show and Sale. Check it out here, and I hope to see you there.