Some people prefer a one-time price to a monthly (or every 3 months) subscription. NINJA MCQ wasn't an option yet when I was studying, but if it had been, I know I would've been sitting there calculating how many months it would have to take me before Wiley would be cheaper than NINJA MCQ, and then determining the likelihood of it taking longer, and assessing the level of risk in each option. AKA, procrastinating studying by applying accounting concepts to real life instead of studying them and actually learning something to help me pass the test. 😛
For example, it's $47 for 3 months for each exam, right? So, let's say you figure it will take the whole 18 months to pass all 4. That's 4.5 months each. That means you'll need to renew once for each exam, so $376 for all 4 exams. Wiley it looks like is up to $575 for all 4 exams, so if you pass with 6 months of access to each exam, you're in good shape. However, Wiley is only a one-year access if you use the online version, so $575 isn't enough for 18 months of studying; you'd have to buy them individually for $600 total to study for 18 months, so the difference increases. They used to sell (not sure if they still do?) a CD/download version that I think could be used forever, but I couldn't find that with a quick Google search. Still, some people would rather buy something outright than have a subscription to it, so that could factor in to decisions for Wiley over NINJA.
Another factor is reputation and history – NINJA MCQs are still quite new, so some people would rather go with something that's got more of a track record.
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