Base loaded antenna
There is no reason to be worried about it. It is absolutely safe for all modulations. The only disadvantage is that the module will get warmer than it will with a standard antenna fully extended. The module getting warmer will lead to the components losing their tuning over time, granted it will take quite some time before this becomes an issue. It is best to have the system checked out once a year if you fly often, regardless of the antenna you are using. If you do not fly that often, you would be fine for a couple years. As a side note, to use the base loaded antenna, you will need a base load antenna adapter for the 8103, that is part number JRPA156.