The service might be of use but my concern is the latency. If I need to use the location variables (in my headline etc), they must be available to me ideally be

The service might be of use but my concern is the latency. If I need to use the location variables (in my headline etc), they must be available to me ideally before the body starts. If they are doing a MaxMind lookup or any lookup of IP from a database, they are not serving cached content from a CDN and hence bound to have more latency then I expect from a library. If my site is big enough with world wide visibility that it needs custom locations, it bet to be fast also