The ant's invisibility feature was a major part of why people used it. I like many others invested in the ant purely for combat use, and never had any intention of building bases with it. The ant was one of my favorite vehicles to use. Now, I guess it's fine that the devs decided to remove the feature. Honestly I don't think it was that overpowered or even used by that many people- as stealth ants are pretty situational and require a ton of cortium to run successfully. But they wanted to remove it and they did, so whatever. That being said, they removed a major feature of the ant that's the equivalent of removing the main canon of a tank (or stealth from a flash). Now that the feature is gone, I don't really want anything to do with the ant, and so all my certs that haven't been refunded already are totally wasted. I imagine this is the case for a lot of other people as well. I don't think it's asking too much for a full cert refund. It wouldn't affect any players who want to continue using the ant negatively as they can just repurchase everything. You could even make the refund optional, similar to the optional cert refund new players get early in starting the game (except specifically for ants). I just don't want to have all the time I spent certing out the ant wasted by no longer having a use for it.