The viability of the product for a solid middle class user really just depends on if Magic+ can fill the type of requests that you'd want to offload in a time-efficient manner or not. Some people in this thread say they're hyper-efficient and specially trained to do so, so it may be worth a try.
Well, except that--as the grandparent post said--the minimum buy is $1000 for 10 hours. That puts it well outside "casual purchase, might come in handy" and into "must have a specific, long-term use in mind" for the typical middle-class income.
Maybe they are choosing to price out those of us who would use occasionally but not often, or maybe it's an acceptable downside to benefits they get from having other people pay that lump up front. (For example, maybe they've found that in the first $200 of spending people aren't convinced, but if they're forced to spend another $800 then they start to appreciate the service more and are less likely to stop using it.)
[1] http://www.nytimes.com/interactive/2012/01/15/business/one-p...