Back when Wrath of Heroes was announced, one of the big questions was whether Warhammer Online subscribers would receive any benefit. Mythic said they were working on it, and it appears they have been. Today they announced the details!
Today our two Warhammer Online games got even closer. Now every Wrath of Heroes player who has an active WAR subscription on the same EA account will benefit from a 50% boost to all gold and experience earned for the complete length of the subscription.
Check out the whole post here.
The bonus boost will stack with ones you can purchase.
As for benefit versus subscription price, they come out to be around equal. 15 days of the 100% Gold Boost costs $10.50 while 15 days of the 100% XP Boost costs $5.25 for a total of $15.75. EDIT: As Kai mentioned, there is no XP cap, so it should always be useful.
As a WAR Subscriber, I like what I see so far... I'll have to think on it some more though.