I'm also curious about these new tires from JConcepts, waiting for availability.
I recently tried various tires on astro-turf, my findings :

2WD front
Schumacher 6592 Stagger Rib are really good and durable, never searched for something else
4WD front
Schumacher 6855 Cactus fusion, really like them, durable
JConcepts 3166 Swaggers 4wd front, good tires but more fuzzy than cactus fusion and little less durable
Proline 8284-103 Prism 2.0 Z3, perfect copy of cactus fusion

Rear
Schumacher 6608 Mini Pin, Good tires but the wear is too fast
Proline 8267-103 Pyramid Z3, Good grip and they are very durable
Proline 8292-103 Hexon Z3, Good grip and very durable, my favourite up to now
JConcepts 3190 Twin pins, really like them at the beginning, but the wear is too fast