It's too bad you're using a .ly domain. The mere association with Libya, and the fact that you're dealing with invoicing, makes me very uncomfortable.
I think you're right it is a current fad - and one that will end soon (all these fads are driven from the lack of available "good" domains I guess). But I am not sure it is a fatal choice; of course .ly is going to be lower performing than .com/.org/etc but I doubt by much - it also has the advantage of being quite "natural" to add/type.
servers are in US and I am in EU if that makes you feel any better.