Seems like a decent price.
5+ Qt jug (or 5 Qts) plus a K&N filter (up to $16.99 value)
$19.99 after some kind of gift card mail-in rebate.
Limit 2 oil changes (so I suppose it's the same limit for the rebate)
ALSO===> There's a "Dream Giveaway" no purchase promo @
http://pennzoilpromos.com/challenger/