There might be trade offs with other options such as waiting or paying full retail print copy price, but the choice is still yours.
Believe it or not, you have complete freedom to find the book elsewhere (like a public library for free or even a local comic shop) or not even bother to finish. There's no obligation for you to purchase the final volume from amazon or anyone else for that matter. You choose to pay the monthly fee and you get to choose to read from what's available. There's no surprises or denial of service here.
Call it a small but definite step forward for the medium.No, it's not a "gotcha" at all. But despite its drawbacks, ComiXology Unlimited is undeniably providing some of the best of the illustrated medium being published today, and it’s helping to ease the cost, both in dollars and shelf space, of collecting entire comic series. The service will change up its offerings regularly, but it seems pegged as more of an exploration service than a fully stocked library. It’s frustrating that, in most cases, only the first or the first few volumes of a series are available to borrow. The technology that ComiXology uses, Guided View technology, allows readers to view comics either full screen or panel by panel on a touchscreen device, with their retina display version, called CMX-HD, doing the same in higher definition. (Marvel already has its own subscription service DC’s resisted.) That might be a deal breaker for die-hard superhero fans, but for readers of the burgeoning selection of great new material - such as Saga and The Walking Dead from Image - or old classics - such as The Peanuts from Fantagraphics - the rental service is still very attractive.
One is that comics from DC and Marvel, which are available for purchase on ComiXology (along with 50,000 other titles), are not included in the unlimited service. ComiXology, a subsidiary of Amazon and a perennial top performer among iPad apps, unveiled ComiXology Unlimited, a $5.99 a month subscription service that lets users “borrow” as many titles as they can read. The most successful online platform for fans of graphic novels, digital comics and manga just bolstered its dominance in the market.