You can have as many domain names poited to a single
site as you wish.
However only one of these domains can be the main or primary name. Any additional names will simply be directed to the primary.
The disavantage is that if you are using Google Adwords marketing you can only use the primary name. In addition all the search engine credibility will be assigned to the primary name only.
This may not be an issue but is certainly something to consider.
We hope this is helpful,
Reason8 Support