Huh. I vastly prefer the Kahrs to the old PPK. I would infinitely prefer a reliable Kahr to a malfunction-prone PPK - though yours may smooth out - no matter a $300 price difference. Not to mention the added power of the 9mm versus the .380. But to each his own.
$800 strikes me as very high for a P9. I see 'em on Gunsamerica for $550-$600 all the time, which is only a little more than the S&W PPKs ($500-ish) on the same site.