love kellerweiss, its my go-to hefeweiss when I am in the mood for one, which isn't all that often, hence why i don't brew that style but once every couple of years.
$10 a six?? man that is highway robbery - I live in a rather high cost-of-living county, and it goes for $7.99 at the grocery, $7.49 at Total Wine, that sux man!
culturing the yeast is a great idea - I've a friend who is a HW nut - he's been using kellerweis yeast since the first six pack hit the shelves, and it is makes a great product - I think he's won 3 medals so far and he's currently fermenting a dunkelweiss with it - can't wait to see how that turns out!