My 5 minute file was 1gb to 1.2, so 10 minutes should be about 2.4gb. (High Bitrate set) If I remember right, that was the case when i viewed my 10 minute clips. So, it shouldn't be an issue. I would think, VIOFO programers would have theorized or calculated that limit, which is why 10 minutes would be the highest loop option available. If they haven't they should taken that consideration for each format they support.
I am going to set it to max bitrate soon. I don't expect it will be much bigger in file size, as it uses a variable bit rate when possible taking into consideration your choice of Bitrate. It does change the quality depending on your bitrate setting.