We're dealing with a high degree of fraud from certain countries and
would like to simply ban all IP's from those countries.

I seem to recall reading here that using the Geo module is more
efficient for this purpose than the GeoIP module.

Currently I have the following in nginx.conf:

geo $country {
include geo.conf;
}

where geo.conf is generated from MaxMind country lite csv database using
geo2nginx.pl supplied with nginx.

In the site config I have multiple if statements like:

server {
...

if ($country = XX) {
return 403;
}

if ($country = YY) {
return 403;
}

if ($country = ZZ) {
return 403;
}

...

}

Is this more efficient than using GeoIP module? Is there a more
efficient way of doing this?

Jim