While I don't disagree that a trial would be nice, in the meantime one way to tell with reasonable certainty how successful you can expect geotagging to be is to download Skyhook's utility Loki (
www.loki.com) to your laptop (or wireless phone, if it supports wifi) and cruise the areas you want to shoot in. If you get a location with Loki, there's a good chance the card will be able to tag (bear in mind that the card will have slightly reduced sensitivity as compared to the laptop).