The title is pretty self-explanatory. $5/100 MB isn't a bad deal for the $42 plan which has only 500 MB to begin with. But, when you go to the $52 plan, $5/100 MB starts to sound quite bad. I'd at least make the overage rate the same as the $62 plan ($5/250 MB). This way, it's still not worth it for heavier users to get the $52 plan over the $62 plan, but the overage rate isn't quite as harsh.