That's what you'd assume, but it doesn't appear to work that way -- if you pay for the "Unlimited" subscription, it doesn't give you access on the iPad (because, somebody decided that an iPad isn't a "computer", I guess). Really disappointing.
It looks like Marvel doesn't actually run the Marvel iPad app -- "Comixology" does, and they don't appear to care if you're a Marvel customer or not, and they blow off all contact about this through the app. As a Marvel customer, using the Marvel app, it's a pretty bizarre customer experience to get responses through that app from a different company, that basically boil down to "not our problem, pls go away".
So, yeah, your $60 will be wasted if you think you can use your subscription on your iPad.